# SSC JE (ME) Mock Test - 5

## 200 Questions MCQ Test Mock Test Series for SSC JE Mechanical Engineering | SSC JE (ME) Mock Test - 5

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Attempt SSC JE (ME) Mock Test - 5 | 200 questions in 120 minutes | Mock test for SSC preparation | Free important questions MCQ to study Mock Test Series for SSC JE Mechanical Engineering for SSC Exam | Download free PDF with solutions
QUESTION: 1

### Study the following arrangement carefully and answer the questions given below :7 1 2 8 2 5 2 7 5 6 4 9 1 9 2 4 1 4 6 4 5 3 2 6 3 7 8 5 1 3 1 5 8 2 7What is the difference between the digit which is seventh from the left end and the digit which is eleventh from the right end of the arrangement?

Solution:

Required difference =2 - 3

≈1

QUESTION: 2

Solution:

Two (1 2, 9 2)

QUESTION: 3

### Study the following arrangement carefully and answer the questions given below :7 1 2 8 2 5 2 7 5 6 4 9 1 9 2 4 1 4 6 4 5 3 2 6 3 7 8 5 1 3 1 5 8 2 7If all the even digits are deleted from the above arrangement, which of the following will be eighth from the right end of the arrangement?

Solution:

After deleting all the even digits, the new arrangement is

8th digit from the right

QUESTION: 4

Study the following arrangement carefully and answer the questions given below :

7 1 2 8 2 5 2 7 5 6 4 9 1 9 2 4 1 4 6 4 5 3 2 6 3 7 8 5 1 3 1 5 8 2 7

How many such 5s are there in the above arrangement, each of which is immediately preceded and also immediately followed by an even digit?

Solution:

One (2 5 2)

QUESTION: 5

Study the following arrangement carefully and answer the questions given below :

7 1 2 8 2 5 2 7 5 6 4 9 1 9 2 4 1 4 6 4 5 3 2 6 3 7 8 5 1 3 1 5 8 2 7

Which of the following is sixth to the left of the twentieth digit from the left end of the above arrangement?

Solution:

Required digit = (20th-6th) from the left or

14th from the left = 9

QUESTION: 6

Select the best one from the given alternatives.

91 : 8 : : 73 : ?

Solution:

The pattern followed here is:

9 - 1 = 8.

Similarly,

7 - 3 = 4

Hence, 4 is the correct answer.

QUESTION: 7

3 partners - A, B, and C have started a business and mutually decided that B’s share of profit will be twice the share of A’s profit but 3/4th the share of C’s profit. If the net profit at the end of the year is Rs. 77877, then find the profit share of B?

Solution:

Let B’s share of profit be Rs x.

B’s profit = 2(A’s profit) ...(i)

→ B’s profit ÷ 2 = A’s profit

→ A’s Profit = x/2

B’s Profit = 3/4 (C’s profit) ...(ii)

→ 4/3 (B’s profit) = C’s profit

→ C’s profit = 4x/3

Net Profit = 77877

A’s profit + B’s profit + C’s profit = 77877

x/2 + x + 4x/3 = 77877

3x + 6x + 8x = 77877 × 6

17x = 77877 × 6

x = 77877 × 6 ÷ 17 = 27486

Hence, Rs. 27486 is the correct answer.

QUESTION: 8

How many meaningful English words can be formed with the letters NKI using each letter only once in each word?

Solution:

Meaningful English words are INK, KIN.

QUESTION: 9

In each of the Questions given below, which one of the five answer figures on the right should come after the problem figures on the left if the sequence were continued?

Solution:

In each problem figure, design "triangle'' slips 1/2 place clockwise direction, the design 'O' slips 1/2 place anti-clockwise direction, and the design ⋆ slips 1/2 place clockwise direction.

QUESTION: 10

In the following question, select the related word from the given alternatives.

Saw : Carpenter : : Axe : ?

Solution:

A carpenter uses a saw to cut and shape wood. Similarly, a woodcutter uses an axe to cut wood.

Hence, Woodcutter is the correct answer.

QUESTION: 11

In these questions, the relationship between different elements is shown in the statements. The statements are followed by conclusions.

Statement A ≤ B

Conclusion I .D< C

Conclusion II. F ≥ D

Solution:

Statement A ≤ BConclusions I .D< C (True)II. F ≥ D (False)

Hence, the only conclusion I is definitely true.

QUESTION: 12

Each of the questions below consists of a question and two statements numbered I and II given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. Read both the statements and give the correct answer.

Amongst four friends A, B, C, and D seated in a straight line facing North, who sits to the immediate right of B?

I. A sits third to the right of B, and C is not an immediate neighbour of B.

II. C sits to the immediate left of A. A sits at one of the extreme ends. D does not sit at the extreme end of the line.

Solution:

From Statement I,

B D C A

Hence, D sits immediate right of B.

From Statement II,

B D C A

Hence, D sits immediate right of B.

QUESTION: 13

Each of the questions below consists of a question and two statements numbered I and II given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. Read both the statements and give the correct answer.

How many brothers does Shilpa have?

I. Deepa, who is Shilpa's sister, has two siblings.

II. Kaushal is the only son of Deepa's parents.

Solution:

From Statement I, we clearly say that Shilpa has one brother and two sisters, herself and Deepa.

QUESTION: 14

Each of the questions below consists of a question and two statements numbered I and II given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. Read both the statements and give the correct answer.

Amongst H, J, K, and L are sitting around a circular table facing the centre. Who sits to the immediate left of H?

I. H sits second to the left of L. K is an immediate neighbour of L.

II. J and H are immediate neighbours of each other. L is an immediate neighbour of J.

Solution:

From Statement I,

From the above figure, we cannot say who sits immediately left of H.

From Statement II,

QUESTION: 15

Each of the questions below consists of a question and two statements numbered I and II given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. Read both the statements and give the correct answer.

On which day of the week did Kiran take an off?

I. Amit correctly remembers that Kiran took an off before Thursday but after Monday.

II. Sneha correctly remembers that Kiran took an 'off after Tuesday but before Friday.

Solution:

From both statements,

According to Amit ⟶ Tuesday, Wednesday

According to Sneha ⟶ Wednesday, Thursday

Hence, on Wednesday Kiran took an off.

QUESTION: 16

Each of the questions below consists of a question and two statements numbered I and II given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. Read both the statements and give the correct answer

Which direction is Sudha facing?

I. If Sunny who is currently facing West, turns 90° towards his left, he would face the same direction as Sudha.

II. If Harry who is currently facing East, turns 90° towards his left, he would face a direction just opposite to the direction Sudha is facing.

Solution:

From Statement I,

Hence, Sudha is facing the South direction.

From Statement II

QUESTION: 17

Point A is 5 m towards the West of point B. Point C is 2 m towards the North of point B. Point D is 3 m towards the East of point C. Point E is 2 m towards the South of point D.

Which of the following points are in a straight line?

Solution:

QUESTION: 18

Point A is 5 m towards the West of point B. Point C is 2 m towards the North of point B. Point D is 3 m towards the East of point C. Point E is 2 m towards the South of point D.

If a person walks 2 m towards the north from point A, takes a right turn and continues to walk, which of the following points would he reach the first?

Solution:

QUESTION: 19

Study the following information to answer the given questions:

P, Q, R, S, T, V, X and Y are seated in a straight line facing North. P sits fourth to the left of V. V sits either sixth from the left end of the line or fourth from the right end of the line. S sits second to right of R. R is not an immediate neighbour of V. T and Q are immediate neighbours of each other but neither T nor Q sits at extreme ends of the line. Only one person sits between T and X. X does not sit at the extreme end of the line.

Who amongst the following sits exactly in the middle of the persons who sit second from the left and the person who sits fifth from the right?

Solution:

Sitting order is

R P S Q T V X Y

QUESTION: 20

Study the following information to answer the given questions:

P, Q, R, S, T, V, X and Y are seated in a straight line facing North. P sits fourth to the left of V. V sits either sixth from the left end of the line or fourth from the right end of the line. S sits second to right of R. R is not an immediate neighbour of V. T and Q are immediate neighbours of each other but neither T nor Q sits at extreme ends of the line. Only one person sits between T and X. X does not sit at the extreme end of the line.

Which of the following represents persons seated at the two extreme ends of the line?

Solution:

Sitting order is

R P S Q T V X Y

R, Y

QUESTION: 21

Study the following information to answer the given questions:

P, Q, R, S, T, V, X and Y are seated in a straight line facing North. P sits fourth to the left of V. V sits either sixth from the left end of the line or fourth from the right end of the line. S sits second to right of R. R is not an immediate neighbour of V. T and Q are immediate neighbours of each other but neither T nor Q sits at extreme ends of the line. Only one person sits between T and X. X does not sit at the extreme end of the line.

What is the position of Q with respect to P ?

Solution:

R P S Q T V X Y

Second to right

QUESTION: 22

Study the following information to answer the given questions:

P, Q, R, S, T, V, X and Y are seated in a straight line facing North. P sits fourth to the left of V. V sits either sixth from the left end of the line or fourth from the right end of the line. S sits second to right of R. R is not an immediate neighbour of V. T and Q are immediate neighbours of each other but neither T nor Q sits at extreme ends of the line. Only one person sits between T and X. X does not sit at the extreme end of the line.

If P is related to Q and S is related to T in a certain way, to which of the following would V be related to following the same pattern?

Solution:

Sitting order is

R P S Q T V X Y

Y (Second Person seated second to the right of first Person)

QUESTION: 23

Study the following information to answer the given questions:

P, Q, R, S, T, V, X and Y are seated in a straight line facing North. P sits fourth to the left of V. V sits either sixth from the left end of the line or fourth from the right end of the line. S sits second to right of R. R is not an immediate neighbour of V. T and Q are immediate neighbours of each other but neither T nor Q sits at extreme ends of the line. Only one person sits between T and X. X does not sit at the extreme end of the line.

How many persons are seated between R and T ?

Solution:

Sitting order is

R P S Q T V X Y

Three (P, S, Q)

QUESTION: 24

In these questions, relationship between different elements is shown in the statements.The statements are followed by conclusions.

Statement F≥G=H; G>J≥K

Conclusions I F≥K

Conclusions II. K

Solution:

statement F≥G=H; G >J≥K

Conclusions I. F≥K (False)

II.KHence, only conclusion II is definitely true.

QUESTION: 25

In these questions, relationship between different elements is shown in the statements.The statements are followed by conclusions.

Statement -L= M ≥N; M >P; L< K

Conclusion I. K>P

Conclusion II. N

Solution:

Statement L= M ≥N; M >P; L< K

Conclusions I. K>P(False)

II. N

Hence, only conclusion II is definitely true.

QUESTION: 26

Which two signs should be interchanged in the following equation to make it correct?

7 -­ 2 + 11 ÷ 1 × 7 = 18

Solution:

1) × and ­-

Given statement: 7 -­ 2 + 11 ÷ 1 × 7 = 18

On interchanging the above signs,

7 × 2 + 11 ÷ 1 ­- 7

= 7 × 2 + 11 ­- 7

= 14 + 11 ­- 7

= 25 -­ 7

= 18

QUESTION: 27

The positions of first and the fourth letters of the word POUNDS are interchanged, similarly, the positions of second and fifth letters and third and sixth letters are interchanged. In the new arrangement thus formed, how many letters are there between the alphabet which is third from the right and the alphabet which is third from the left, in the English alphabetical order?

Solution:

Given word = POUNDS

After interchanged, new word =NDSPOU

Hence, two letters (Q, R) are between the alphabet, third from the right (P) and third from the left (S).

QUESTION: 28

How many such pairs of letters are there in the word QUICKLY, each of which has as many letters between them in the word (in both forward and backward directions) as they have between them in the English alphabetical order?

Solution:

Hence, the number of such pairs are IK, IL, KL, LQ.

QUESTION: 29

Among five boxes numbered 1,,2,3,4 and 5 each has a different weight. Box no. 1 is heavier than box no' 5 but lighter than box no. 3. Box no. 4 is heavier than box no.3 but lighter than box no. 2. Which of the following represents the boxes which are the heaviest and the lightest respectively?

Solution:

Box no.2 >Box no.4 >Box no.3 >Box no. 1 >Box no.5

Hence, Box no. 2 is the heaviest, and Box no. 5 is the lightest.

QUESTION: 30

In these questions, relationship between different elements is shown in the statements. The statements are followed by conclusions.

Statement P< Q = R ≥ T; S ≥ T

Conclusions I .T ≤ Q

Conclusions II. R > P

Solution:

Statement P< Q = R ≥ S ≥ T

Conclusions I. T ≤ Q (True) II. R >P (True)

Hence, both conclusions are definitely true.

QUESTION: 31

In these questions, relationship between different elements is shown in the statements.The statements are followed by conclusions.

Statement- U >A = I ≤ O ≤ E

Conclusion I. I ≤ E

Conclusion II. o >U

Solution:

Statement U >A = I ≤ O ≤ E

Conclusions I. I ≤ E (False)

II. o >U (False)

Hence, only conclusion I is definitely true.

QUESTION: 32

Study the following information carefully and answer the given questions :

A, B, C, D, E, F, G and H are sitting around a square table facing the centre in such a way that four of them sit at four corners of the square while four sit in the middle of each of the flour sides.

(a) A sits second to right of F. F sits in the middle of one of the sides of the table

(b) G who does not sit at any of the corners of the table sits second to the right of D

(c) Only two people sit between D and B (taken from one side)

(d) C is not an immediate neighbour of G

(e) H is sits second to left of B

(f) E is not an immediate neighbour of G or F

Four of the following five are alike in a certain way based on their seating positions in the above arrangement and so form a group. Which is the one that does not belong to that group?

Solution:

(All others sit middle of the each side)

QUESTION: 33

Study the following information carefully and answer the given questions :

A, B, C, D, E, F, G and H are sitting around a square table facing the centre in such a way that four of them sit at four corners of the square while four sit in the middle of each of the flour sides.

(a) A sits second to right of F. F sits in the middle of one of the sides of the table

(b) G who does not sit at any of the corners of the table sits second to the right of D

(c) Only two people sit between D and B (taken from one side)

(d) C is not an immediate neighbour of G

(e) H is sits second to left of B

(f) E is not an immediate neighbour of G or F

What will come in place of the question mark (?) based upon the given seating arrangement?

AE EH HF?

Solution:

One more person sits in each successive pair of person.

Hence, three persons (C, A, E) are sitting between F and D.

QUESTION: 34

Study the following information carefully and answer the given questions :

A, B, C, D, E, F, G and H are sitting around a square table facing the centre in such a way that four of them sit at four corners of the square while four sit in the middle of each of the flour sides.

(a) A sits second to right of F. F sits in the middle of one of the sides of the table

(b) G who does not sit at any of the corners of the table sits second to the right of D

(c) Only two people sit between D and B (taken from one side)

(d) C is not an immediate neighbour of G

(e) H is sits second to left of B

(f) E is not an immediate neighbour of G or F

How many persons sit between A and H when counted in anti-clockwise direction from A?

Solution:

QUESTION: 35

Study the following information carefully and answer the given questions :

A, B, C, D, E, F, G and H are sitting around a square table facing the centre in such a way that four of them sit at four corners of the square while four sit in the middle of each of the flour sides.

(a) A sits second to right of F. F sits in the middle of one of the sides of the table

(b) G who does not sit at any of the corners of the table sits second to the right of D

(c) Only two people sit between D and B (taken from one side)

(d) C is not an immediate neighbour of G

(e) H is sits second to left of B

(f) E is not an immediate neighbour of G or F

Who sits exactly between F and A?

Solution:

QUESTION: 36

Study the following information carefully and answer the given questions :

A, B, C, D, E, F, G and H are sitting around a square table facing the centre in such a way that four of them sit at four corners of the square while four sit in the middle of each of the flour sides.

(a) A sits second to right of F. F sits in the middle of one of the sides of the table

(b) G who does not sit at any of the corners of the table sits second to the right of D

(c) Only two people sit between D and B (taken from one side)

(d) C is not an immediate neighbour of G

(e) H is sits second to left of B

(f) E is not an immediate neighbour of G or F

What is the position of F with respect to C?

Solution:

QUESTION: 37

Three of the following four letter-clusters are alike in a certain way and one is different. Find the odd one out.

Solution:

The pattern followed here is:

Hence, the odd one among the given options is FDAV.

QUESTION: 38

In the question below, which one of the given responses would be a meaningful order of the following words?

1. Century

2. Half Century

3. Triple Century

4. Double Century

Solution:

The Logical order of runs in Cricket is Half Century, Century, Double Century and Triple Century.

Hence, the correct answer is 2, 1, 4 and 3.

QUESTION: 39

Select the option that is most like the given set.

(9, 29, 67)

Solution:

The pattern followed here is,

(9,29,67)→(23+1)=9;33+2=29;43+3=67)

Similarly,

(2,10,30)→(13+1=2,23+2=10;33+3=30)

Hence, (2, 10, 30) is the correct answer.

QUESTION: 40

If each of the alphabets of the word SALIENT is arranged in alphabetical order from left to right and then, each vowel in the new word thus formed is changed to the next letter in the English alphabetical series and each consonant is changed to the previous letter in the English alphabetical series. Which of the following will be third from the left?

Solution:

Given word =SALIENT

Alphabetical order of the given word

A+1=B

E+1=F

I+1=J

L-1=K

N-1=M

S-1=R

T- 1=S

Hence, J letter will be third from the left.

QUESTION: 41

Direction: In the following question, select the related word from the given alternative.

Dread : Misgiving :: Naivety : ?

Solution:

As per the question,

Dread is the synonym of Misgiving

Dread → a feeling of fear

Similarly, Naive is the synonym of Gullible.

Naivety → tendency to believe anyone easily

Hence, the correct answer is gullibility.

QUESTION: 42

The following questions are based upon the alphabetical series given below :

D L U A E N I O G K S V R M P B H F

If in a certain code'GLAD'is coded as'SANU'and'BUMP' is coded as 'FEBH'how will'SKID'be coded in the same code language?

Solution:

As, And

G+2=S B+2=F

L+2=A U+2=E

A+2=N M+2=B

D+2=U P+2=H

similarly,

S+2=R

K+2=V

I+2=G

D+2=U

QUESTION: 43

The following questions are based upon the alphabetical series given below :

D L U A E N I O G K S V R M P B H F

If 'LU' is related to 'EO' and 'SV' is related to 'MH' in a certain way, to which of the following is NI related to, following the same Pattern?

Solution:

QUESTION: 44

The following questions are based upon the alphabetical series given below :

D L U A E N I O G K S V R M P B H F

What will come in place of question (?) mark in the following series based on the above alphabetical series?

Solution:

QUESTION: 45

Study the following information to answer the given questions :

In a certain code, 'he is waiting there' is written as 'la pa ro ta', 'there is the train' is written as 'zo ro ji la', 'waiting at the station' is written as 'ma ta fu ji' and 'is this a station' is written as 'fu bi ro vi'.

What is the code for'at'?

Solution:

He is waiting there-----la pa ro ta

there is the train-------zo ro ji la

waiting at the station-----ma ta fu ji

Is this a situation -------fu bi ro vi

Hence at -> ma

QUESTION: 46

Study the following information to answer the given questions :

In a certain code, 'he is waiting there' is written as 'la pa ro ta', 'there is the train' is written as 'zo ro ji la', 'waiting at the station' is written as 'ma ta fu ji' and 'is this a station' is written as 'fu bi ro vi'.

What does 'la' stand for?

Solution:

He is waiting there-----la pa ro ta

there is the train-------zo ro ji la

waiting at the station-----ma ta fu ji

Is this a situation -------fu bi ro vi

hence la → there

QUESTION: 47

Study the following information to answer the given questions :

In a certain code, 'he is waiting there' is written as 'la pa ro ta', 'there is the train' is written as 'zo ro ji la', 'waiting at the station' is written as 'ma ta fu ji' and 'is this a station' is written as 'fu bi ro vi'.

What is the code for'he'?

Solution:

He is waiting there-----la pa ro ta

there is the train-------zo ro ji la

waiting at the station-----ma ta fu ji

Is this a situation -------fu bi ro vi

Hence he=pa

QUESTION: 48

Study the following information to answer the given questions :

In a certain code, 'he is waiting there' is written as 'la pa ro ta', 'there is the train' is written as 'zo ro ji la', 'waiting at the station' is written as 'ma ta fu ji' and 'is this a station' is written as 'fu bi ro vi'.

Which of the following represents 'the train station'?

Solution:

He is waiting there-----la pa ro ta

there is the train-------zo ro ji la

waiting at the station-----ma ta fu ji

Is this a situation -------fu bi ro vi

the → ji, train → zo, station → fu

Hence, 'the train station' → ji zo fu or fu ji zo

QUESTION: 49

Study the following information to answer the given questions :

In a certain code, 'he is waiting there' is written as 'la pa ro ta', 'there is the train' is written as 'zo ro ji la', 'waiting at the station' is written as 'ma ta fu ji' and 'is this a station' is written as 'fu bi ro vi'.

Which of the following may represent 'guard is waiting'?

Solution:

He is waiting there-----la pa ro ta

there is the train-------zo ro ji la

waiting at the station-----ma ta fu ji

Is this a situation -------fu bi ro vi

is → ro. waiting → ta

Hence, 'guard is waiting' → ki or ta or ta ki ro

QUESTION: 50

Directions: The question consists of two statements, an assertion (A) and a reason (R). Read both the statements and decide which of the following answer choice correctly depicts the relationship between these two statements.

Assertion (A): Lower GDP rate means a proportionate decline in per capita income.

Reason (R): The contribution of the agriculture sector in the Indian economy is much higher than the world's average.

Solution:

Both A and R are true, but R is not the correct explanation of A.

Here, both the statements are true.

A decline in GDP would mean unemployment and declining business revenues and consumer spending thereby causing a decline in the per capita income.

India being an agrarian country, its agriculture sector has a huge contribution to the economy.

But the assertion and reason given are not related.

QUESTION: 51

Sher Shah defeated Humayun in the ________ and assumed the title 'Sher Shah'.

Solution:

QUESTION: 52

When was the revolt of 1857 started in Dum Dum Arsenal - a British military facility located near the town of Dum Dum in modern West Bengal?

Solution:

The revolt of 1857 was started in the region of Dum Dum Arsenal on 26th February 1857.

Captain Neville promoted the idea of using Mark IV cartridges (Dum Dum bullets) at Dum Dum Arsenal.

Dum Dum Arsenal - a British military facility located near the town of Dum Dum in modern West Bengal.

QUESTION: 53

The first session of the constituent assembly took place on which of the following dates?

Solution:

The first meeting of the Constituent Assembly of India took place in Constitutional Hall, New Delhi, on 9th December 1946. Dr. Sachchidananda Sinha was the first president of the Constituent Assembly. In the first meeting, the assembly adopted an ‘Objective Resolution’ which later became the preamble of the constitution. It appointed various committees. The report of the committees formed the basis on which the first draft of the constitution was prepared. It reassembled on 14 August 1947 as Constituent Assembly for independent India.

After partition, Dr. Rajendra Prasad became the president of the Constituent Assembly of Independent India. Professor Harendra Coomar Mookerjee was Vice President of the Constituent Assembly. While Dr. Rajendra Prasad later became President of India, Prof. HC Mookerjee became the first Governor of West Bengal.

QUESTION: 54

Who among the following appoints the Attorney general of India?

Solution:

QUESTION: 55

Which of the following won the Outstanding Performance by a Female Actor in a Drama Series award at the 26th Annual Screen Actors Guild Awards?

Solution:

Winners of the 26th Annual Screen Actors Guild Awards have been announced.

The event was held on 19 Jan 2020 at the Shrine Auditorium in Los Angeles, USA.

The award honours the year’s biggest achievements in TV and film.

The Screen Actors Guild Awards are presented by SAG-AFTRA, which made its debut in 1995.

Sam Rockwell received an Outstanding Performance by a Male Actor in a Television Movie or Miniseries.

Outstanding Performance by a Female Actor in a Drama Series was awarded to Jennifer Aniston.

Outstanding Performance by a Male Actor in a Drama Series was given to Peter Dinklage.

Outstanding Performance by a Male Actor in a Comedy Series was given to Tony Shalhoub.

QUESTION: 56

In the context of Mughal administration, the term 'zabt' referred to the ________ system.

Solution:

In the context of the Mughal administration, the term 'zabt' referred to the revenue.

In the reign of the Akbar empire, Todar mal was a finance minister who introduced a revenue system which is called zabt.

Todar Mal was one of the navratnas from his Nine Jewels.

This revenue system is implemented on crop yields for 10 years.

QUESTION: 57

The lowest layer of atmosphere is known is:

Solution:

The troposphere is the lowest layer of the Earth's atmosphere. The atmosphere is comprised of layers based on temperature. These layers are the troposphere, stratosphere, mesosphere, and thermosphere. A further region at about 500 km above the Earth's surface is called the exosphere.

QUESTION: 58

Which organism causes Filariasis?

Solution:

QUESTION: 59

________ is the ore of lead.

Solution:

QUESTION: 60

How many members are there in the Public Accounts Committee of Parliament?

Solution:

The Public Accounts Committee (PAC) is a committee of selected members of Parliament, constituted by the Parliament of India, for the auditing of the revenue and the expenditure of the Government of India. It consists of 22 members (15 from Lok Sabha and 7 from Rajya Sabha)

QUESTION: 61

In which session of the Congress was the slogan of the Simon Commission’s boycott?

Solution:

Simon Commission was formed in the year 1928, under the chairmanship of Sir John Allsebrook Simon. It was a group of seven British Parliament members who came to India to study constitutional reform in Britain’s most important colonial dependency.

Simon commission was boycotted by the Indian National Congress at its Madras session in the year 1927.

The boycott of the commission was done to challenge Lord Birken head, then-Secretary of State for India, in order to draft a constitution that would be acceptable to the general public of India.

QUESTION: 62

Which among the following is the name of the rocket launched by Vikram Sarabhai Space Centre of ISRO to study changes in the earth’s upper atmosphere during the eclipse? (Dec 2019)

Solution:

Rohini 200 is the name of the rocket launched by Vikram Sarabhai Space Centre of ISRO to study changes in the earth’s upper atmosphere during the eclipse.

The rocket was launched from Thumba in Thiruvananthapuram, Kerala which is a major space research centre of the Indian Space Research Organisation.

Rohini 200 is a sounding rocket which is an instrument-carrying rocket designed to take measurements and perform scientific experiments during its sub-orbital flight.

QUESTION: 63

What is the SI unit of Density?

Solution:

QUESTION: 64

Which of the following is NOT a metamorphic rock?

Solution:

Diorite is an example of an igneous rock.

QUESTION: 65

Who among the following wrote the book 'Epitome'?

Solution:

"Epitome" was written by Justin.

Justin was a Greek scholar.

He wrote about the Mauryan period and called Chandragupta Maurya as Sandracottus.

Deimachus was the Greek Ambassador in the court of Bindusara.

Megasthenes was the Ambassador in the court of Chandragupta Maurya.

Megasthenes wrote the book "Indika".

Strabo wrote the book "Geography".

QUESTION: 66

Department of Industrial Policy and Promotion comes under which Ministry?

Solution:

Department of Industrial Policy and Promotion comes under the Commerce and Industry Ministry.

The Department of Industrial Policy and Promotion primarily has a role in the formulation and implementation of industrial policy and strategies for industrial development in conformity with the development needs and national objectives etc.

It monitors the industrial growth and production, in general, and selected industrial sectors.

The Department was originally established in 1995 and was reconstituted in the year 2000 with the merger of the Department of Industrial Development.

The first Minister of Commerce and Industry of independent India was Syama Prasad Mukherjee.

QUESTION: 67

'Sardar Sarovar Dam' is on which of the following rivers?

Solution:

The Sardar Sarovar Dam is a gravity dam on the Narmada river near Navagam, Gujarat in India.

It is a part of the Narmada Valley Project, a large hydraulic engineering project involving the construction of a series of large irrigation and hydroelectric multi-purpose dams on the Narmada river.

QUESTION: 68

The IUCN Red List provides data on ________.

Solution:

The IUCN Red List of threatened species is an inventory that lists all the species and sub-species that are threatened, that is, on the verge of extinction.

IUCN Red List of Threatened Species founded in 1965 with the aim to spread awareness among the masses about the extinction of species and the need for conservation.

International Union for Conservation of Nature (IUCN), was established on 5 October 1948 in France.

QUESTION: 69

Which Desert-country pair is wrongly matched?

Solution:

Great Victoria is located in Australia, not South America. Great Victoria is the largest desert in Australia.

Kalahari covers Botswana, Namibia, South Africa in Africa.

Mojave covers California, Nevada, Utah, and Arizona in the United States.

Taklamakan desert is in China.

QUESTION: 70

The process of forming a thick oxide layer of aluminium is known as ________.

Solution:

The process of forming a thick oxide layer of Aluminium is known as Anodizing.

The process is called anodizing because the part to be treated forms the anode of an electrolytic cell.

Anodizing is an electrochemical process that converts the metal surface into a decorative, durable, corrosion-resistant, anodic oxide finish.

The anodic oxide structure originates from the aluminium substrate and is composed entirely of aluminium oxide.

QUESTION: 71

Which of the following communication modes provides bidirectional data transmission?

Solution:

There are three types of transmission modes. In simplex mode, data can be sent only through one direction i.e. communication is unidirectional. In half-duplex system, we can send data in both directions but it is done one at a time that is when the sender is sending the data then at that time we can’t send the sender our message. In full-duplex system, data can be sent in both directions simultaneously.

QUESTION: 72

Which of the following will be host to India’s first war memorial for service animals including dogs, horses, and mules?

Solution:

Meerut in Uttar Pradesh will be host to India’s first war memorial for service animals including dogs, horses, and mules.

This place will dedicate itself to the contributions of animals who have helped the army in counter-insurgency operations in Kashmir and in the battlefield during the Kargil War.

The memorial will come up at the Remount and Veterinary Corps (RVC) Centre and College.

Uttar Pradesh: State Animal - Barasingha

State Bird - Sarus crane

QUESTION: 73

Marble is a metamorphic rock of _______.

Solution:

Marble is the metamorphic rock of limestone. It is commonly known for its use in sculpture and building.

QUESTION: 74

In January 2020, Union Home Minister released a book ‘Karmayoddha Granth’. On whose life is the book based on

Solution:

Union Home Minister released a book ‘Karmayoddha Granth’ on the life of Prime Minister Narendra Modi.

A ‘Karmayoddha’ is a man with a beating heart for people, a statesman, a hard taskmaster, an able administrator, and an ideal leader who leads by example.

All these qualities have been personified by Narendra Modi.

QUESTION: 75

Which of the following games will be included in the Khelo India for the first time in January 2020?

Solution:

6500 athletes from 37 teams took part in the 3rd Khelo India youth games in Guwahati beginning from the 10th of January.

Lawn ball and cycling were included in the Khelo India for the first time.

A total of 20 competitions was held at 11 venues in and around Guwahati.

The Assam govt gave Rs 1 lakh for Gold, Rs 75,000 for silver, and Rs 50,000 for bronze medalist Assam players.

QUESTION: 76

Butter Paper is an example of ________ object.

Solution:

Butter Paper is an example of a translucent object.

Butter Paper is considered translucent since it allows light to travel partially through it.

It has a fainter shadow and it lets light pass through it.

Translucent objects are objects through which light is able to pass, but through which objects are not clearly visible.

Examples of translucent objects are wax paper or frosted glass-like ones one might find in a shower.

Opaque is not capable of having light pass through.

QUESTION: 77

Who got the Saraswati Samman award in 2019?

Solution:

Eminent Sindhi writer Vasdev Mohi will be conferred with 29th Saraswati Samman.

He has been selected for this prestigious literary award for his collection of short stories- Chequebook.

Saraswati Samman carries a cash award of 15 lakh rupees, a citation, and a plaque.

Mr. Mohi has authored 25 books of poetry, stories, and translations.

The Saraswati Samman is an annual award for outstanding prose or poetry literary works in any of the 22 languages of India listed in Schedule VIII of the Constitution of India.

QUESTION: 78

Who has become the fastest batsman to reach 1000 runs in T20 International cricket as captain and only the sixth overall to achieve the feat?

Solution:

Virat Kohli broke another batting record, as he became the fastest to reach 1000 runs in T20 International cricket as captain and only the sixth overall to achieve the feat.

He is only the second Indian after MS Dhoni (1112 runs from 62 games) to achieve this feat.

He achieved it in the 30th innings.

Virat Kohli has also overtaken his teammate Rohit Sharma on the list of most runs scored in T20I cricket.

QUESTION: 79

What is the rank of India in the EIU Democracy Index, released in January 2020?

Solution:

The EIU Democracy Index was released on 22 January 2020.

India slipped 10 places to 51st position in the 2019 Democracy Index's global ranking.

Norway is at the top with an overall score of 9.71 while North Korea is at the bottom of the index.

Overall, 2019 marked the worst year of global democracy score since 2006 when the rankings were first published.

According to The Economist Intelligence Unit’s measure of democracy, almost one-half of the world’s population live in a democracy of some sort, although only 5.7% reside in a full democracy.

More than one-third of the world’s population lives under authoritarian rule, with a large share being in China.

QUESTION: 80

WTO was founded on _________.

Solution:

WTO stands for World Trade Organisation.

It was founded on 1st January 1995

It was set up under the Marrakesh Agreement.

The agreement was signed in Marrakesh, Morocco, by 124 nations on 15 April 1994

It replaced the General Agreement on Trade and Tariff (GATT).

It is headquartered in Geneva, Switzerland.

The current total members of WTO is 164

QUESTION: 81

Who was the President of the Indian National Congress during the Quit India Movement?

Solution:

Abul Kalam Azad was the President of the Indian National Congress during the Quit India Movement which took place in 1942.

He was elected twice as the President, first in 1923 and the second time in 1940. His second tenure lasted till 1946 as there were no re-elections since maximum members of the Congress were in jail due to their participation in the Quit India Movement.

Post-independence, he became the first Minister of Education on 15 August 1947.

QUESTION: 82

Before taking over the Mughal throne, Shah Jahan was called ________.

Solution:

Shah Jahan was born on 5 January 1592 as "Shahab-ud-din Muhammad Khurram".

Khurram which means joyous was the name given to him by his grandfather Akbar who was very close to him.

Shah Jahan was the fifth Mughal emperor. He was preceded by his father Jahangir and succeeded by his son Aurangzeb.

It was in 1617 that after Prince Khurram managed to secure the southern borders and restored the Mughal empire's control over the Deccan region that Jahangir granted him the title Shah Jahan which is Persian for "King of the World".

QUESTION: 83

State Land Reform is under which schedule of the Indian Constitution?

Solution:

The first amendment to the Indian Constitution added the Ninth Schedule to it in 1951.

It ensured that the laws related to land reforms were not challenged in courts for violation of fundamental rights.

QUESTION: 84

Bricks market can usually be kept in which category of the market?

Solution:

Bricks market refers to a traditional street-side business that deals with its customers face-to-face in an office or store that the business owns or rents. For Example the local grocery store.

QUESTION: 85

'Megaptera novaeangliae' is commonly known as ________.

Solution:

'Megaptera novaeangliae' is commonly known as a Humpback whale.

It means 'Big wing of new England'.

These are found in almost all the oceans in the world.

QUESTION: 86

________ is the centre of the reflecting surface of a spherical mirror.

Solution:

The centre of the reflecting surface of a spherical mirror is called a pole.

The centre of the sphere of which the spherical mirror forms a part is termed as the centre of curvature.

The radius of curvature is the distance between the pole and the centre of curvature.

QUESTION: 87

Sodium metal is stored in _______.

Solution:

Sodium metal is stored in Kerosene.

Metals such as sodium, Potassium are highly reactive, and they catch fire if they are kept in open, hence these metals are immersed in kerosene to prevent their oxidation.

Reactive elements displace the less reactive elements in a chemical reaction.

The reactive element loses electrons readily to attain stable electronic configuration and thus reduce another element and oxidizes itself.

Reactive metals are found on top of the reactivity series.

The order of reactivity of metals is given below.

QUESTION: 88

In January 2020, which of the following has planned to invest nearly \$1 billion in India over the next five years towards the development of new technologies and products?

Solution:

Mastercard has planned to invest nearly \$1 billion in India over the next five years towards the development of new technologies and products.

The proposed investment will be made in India operations, which includes an R&D facility at Pune and another centre at Vadodara,

Mastercard has also launched its Team Cashless India programme to engage with merchants and consumers across the country.

QUESTION: 89

Match the following:

Solution:

QUESTION: 90

________ was awarded the Nobel Prize for his is investigations on carotenoids, flavins, and vitamins A and B2

Solution:

The correct answer is option 3, i.e., Paul Karrer

He was a Swiss organic chemist best known for his research on vitamins.

He along with Norman Haworth won the Nobel Prize for Chemistry in 1937 for his investigations on carotenoids, flavins, and vitamins A and B2.

QUESTION: 91

Which law of thermodynamics defines the concept of temperature?

Solution:

The Zeroth law of thermodynamics defines temperature. It states that “If two systems are in thermal equilibrium with the third system, then they are in thermal equilibrium with each other.”

Zeroth law – the concept of temperature

First law – the concept of internal energy

Second law – the concept of entropy

QUESTION: 92

How many States and UTs participated in the Republic Day Parade 2020 in New Delhi?

Solution:

16 States and UTs and 6 Central Ministries participated in the Republic Day Parade 2020 in New Delhi.

The Tableau of Gujarat is on the theme Rani ki Vav - Jal Mandir.

Punjab's Tableau is on the theme '550th Birth Anniversary of Guru Nanak Dev Ji'.

Odisha will showcase the famous Rukuna Rath Yatra of Lord Lingaraj.

Meghalaya's Tableau will showcase the Double Decker Living Root Bridge.

Chattisgarh will showcase the artistic beauty of the state.

Jammu and Kashmir Tableau will showcase the Union Territories's Back to Village programme which was launched last year with the aim to empower villages and Panchayats.

QUESTION: 93

Which of the following statements is true?

Solution:

Kidneys are the main excretory organs in human beings. They are bean-shaped organs that are located in the upper abdomen, against the back muscles.

A kidney is mainly divided into two parts, the outer cortex, and the inner medulla.

Each kidney is made up of millions of ducts called nephrons which are the structural and functional unit of a kidney.

QUESTION: 94

Recently, eminent Odissi dancer, Minati Mishra passed away. For which year did she receive the Odisha Sangeet Natak Akademi award?

Solution:

Eminent Odissi dancer and Padma Shri awardee Minati Mishra passed away in Switzerland.

A recipient of the Odisha Sangeet Natak Akademi award for 1975, Minati received the Padma award in 2012.

Besides, Minati acted in five Odia films.

She was also an A-Grade artist at AIR and a recipient of the Sangeet Prabhakar title for Hindustani vocal music.

QUESTION: 95

Which among the following comes under the Union List of the Indian Constitution?

I. Defense

III. Banking

Solution:

Union List, also known as List-I, is a list of 100 items that were given in the 7th schedule in the Indian Constitution.

Defense, Banking and Inter-State Trade, and Commerce all come under this list.

QUESTION: 96

A freely suspended magnet always aligns in the ________direction.

Solution:

A freely suspended magnet always aligns in the North-South direction.

A freely suspended magnet does not show exact geographical South and North because the magnetic axis and geographical axis of the Earth do not coincide.

Earth itself behaves as a magnet which causes a freely suspended magnet (or magnetic needle) to point always in a particular direction: North and South.

The South Pole of the Earth's magnet is in the geographical North because it attracts the North Pole of the suspended magnet and vice versa.

Earth's magnetism is due to the magnetic effect of current which is flowing in the liquid core at the centre of the Earth.

Earth is a huge electromagnet. Permanent magnets cannot exits above 650 celsius.

QUESTION: 97

What is the theme of International Customs Day 2020?

Solution:

International Customs Day is observed on 26 January every year.

It recognizes the role of customs officials and agencies and focuses on the working conditions and challenges that customs officers face in their jobs.

The theme for the year 2020 is “Customs fostering Sustainability for People, Prosperity and the Planet”.

The day was instituted by the World Customs Organization (WCO) in 1953.

QUESTION: 98

How many times the name Ashoka does appear in the inscriptions?

Solution:

The name Ashoka appears only 4 times in the inscriptions.

It appears 3 times in copies of Minor Rock Edicts I at Karnataka and 1 time in MP.

The inscriptions mention Devanampiya 'piyadasi' in the place of Ashoka.

QUESTION: 99

What is the thickness of the crust on the continental masses (in km)?

Solution:

Continental crust is thicker, 22 miles (35 km) on average, and less dense than oceanic crust, which accounts for its mean surface elevation of about 3 miles (4.8km) above that of the ocean floor.

QUESTION: 100

________ is the study or cultivation of fruit crops.

Solution:

Pomology is the study or cultivation of fruits.

The science of vegetable growing is Olericulture.

Systemology is a field representing the organised body of knowledge about systems.

QUESTION: 101

The ratio of Young’s Modulus of elasticity to the bulk modulus of elasticity for Poisson’s ratio 0.2 is

Solution:

Concept:

E = Young's Modulus of elasticity = Stress / strain

G = Shear Modulus or Modulus of rigidity = Shear stress / Shear strain

ν = Poisson’s ratio = - lateral strain / longitudinal strain

K = Bulk Modulus of elasticity = Volumetric stress / Volumetric strain

Relation between E, K and ν

E = 2G (1 + ν)

E = 3K (1 - 2ν)

Calculation:

E = 3K (1 - 2ν)

QUESTION: 102

Percentage of carbon in steel is _____.

Solution:

Steel is an alloy of iron and carbon, along with small amounts of other alloying elements or residual elements as well. The plain iron-carbon alloys (Steel) contain 0.002 - 2.1% by weight carbon. For most of the materials, it varies from 0.1-1.5%.

There are 3 types of plain carbon steel:

(i) Low-carbon steels: Carbon content in the range of < 0.3%

(ii) Medium carbon steels: Carbon content in the range of 0.3 – 0.6%.

(iii) High-carbon steels: Carbon content in the range of 0.6 – 1.4%.

QUESTION: 103

The size of BUE in metal cutting increases with

Solution:

Factors reducing the BUE formation are

- By increasing cutting speed

- Increasing rake angle as it will decrease the force

- By decreasing the feed

- By reducing the depth of cut

- By the use of cutting fluid

So out of given options, the BUE increases with the large uncut chip thickness. The remaining all options will decrease BUE formation.

QUESTION: 104

Which of the following statements does NOT apply to the volumetric efficiency of a reciprocating air compressor?

Solution:

In actual compressors, a small clearance is left between the cylinder head and piston to accommodate the valves and to take care of thermal expansion and machining tolerances.

A large clearance volume results in low volumetric efficiency and hence large cylinder dimensions increase the contact area between the piston and cylinder and so, increases friction and work.

Volumetric efficiency is given by:

Where c = Clearance ratio.

P2/P1=Pressure;ratio

As the clearance ratio increases, the volumetric efficiency of the reciprocating compressor decreases as the pressure ratio increases.

QUESTION: 105

According to newton’s law of viscosity, the shear is directly proportional to:

Solution:

Hence shear stress is proportional to the velocity gradient.

QUESTION: 106

In limits and fits system, basic shaft system is one whose

Solution:

Hole basis system: The hole is kept as a constant member (i.e. when the lower deviation of the hole is zero).

Shaft basis system: When the shaft is kept as a constant member (i.e. when the upper deviation of the shaft is zero).

QUESTION: 107

The work done equals smallint pdv for

Solution:

The non-flow work done by the system (only on the quasi-static process) is given by:

Wnon−flow=mathopsmallintlimits12pdV

Work done in a flow process (any process):

Wflow−process=−mathopsmallintlimits12VdP

QUESTION: 108

Which material has the highest value of poisson's ratio?

Solution:

Elastic Rubber: 0.5

Wood: Because wood is orthotropic, 12 constants are required to describe elastic behaviour: 3 moduli of elasticity, 3 moduli of rigidity, and 6 Poisson’s ratios (vary from 0.02 to 0.47). These elastic constants vary within and among species and with moisture content and specific gravity.

Copper: 0.33

Steel: 0.27 - 0.30

QUESTION: 109

The crystal structure of Aluminium is

Solution:

Crystal structure of Material

FCC: - Ni, Cu, Ag, Pt, Au, Pb, Al, Austenite or Ƴ-iron

BCC: - V, Mo, Ta, W, Ferrite or α-iron, δ-ferrite or δ-iron

HCP: - Mg, Zn

Cobalt: - HCP < 420°C, FCC > 420°C

Chromium: - HCP < 20°C, BCC > 20°C

Glass: - Amorphous

QUESTION: 110

The major constituents of fuel are

Solution:

Fuel is an explosive substance containing carbon as the main constituent, which on proper burning gives a large amount of heat, which can be used economically for domestic and industrial purposes. E.g., Wood, Charcoal, Coal, Kerosene, Petrol, Producer gas, Oil gas, LPG, etc.

The major composition of all fuels is carbon and hydrocarbons, so they are also called hydrocarbons.

During the process of combustion of a fuel (like coal), the atoms of carbon, hydrogen, etc., combine with oxygen with the simultaneous liberation of heat at a rapid rate.

Fuel + Oxygen → Products + Heat

QUESTION: 111

Which of the following is a medium head turbine in which water flows inwards radially?

Solution:

High head turbine: In this type of turbine, the net head varies from 150m to 2000m or even more, and these turbines require a small quantity of water. Example: Pelton wheel turbine.

Medium head turbine: The net head varies from 30m to 150m, and also, these turbines require a moderate quantity of water. Example: Francis turbine.

Low head turbine: The net head is less than 30m, and also, these turbines require a large quantity of water. Example: Kaplan turbine.

QUESTION: 112

Pick up the correct statement -

Solution:

Required Properties of Ideal Refrigerant:

1) The refrigerant should have a low boiling point and a low freezing point.

2) It must have low specific heat and high latent heat. Because high specific heat decreases the refrigerating effect per kg of refrigerant and high latent heat at low temperature increases the refrigerating effect per kg of refrigerant.

3) It must have high critical pressure and temperature to avoid large power requirements.

4) The pressures required to be maintained in the evaporator and condenser should be low enough to reduce the material cost and must be positive to avoid leakage of air into the system.

5) It should have a low specific volume to reduce the size of the compressor.

6) It must have high thermal conductivity and a high heat transfer coefficient to reduce the area of heat transfer in the evaporator and condenser.

7) It should be non-flammable, non-explosive, non-toxic, and non-corrosive.

8) It should not have any bad effects on the stored material or food when any leak develops in the system.

9) It must have high miscibility with lubricating oil, and it should not react properly with lubricating oil in the temperature range of the system.

10) It should give high COP in the working temperature range. This is necessary to reduce the running cost of the system.

QUESTION: 113

Cavitation is caused by

Solution:

Cavitation is the formation of gas bubbles of a flowing liquid in a region where the pressure of the liquid falls below its vapour pressure i.e., low pressure.

Cavitation is the phenomenon of the formation of vapour bubbles of a flowing liquid in a region where the pressure of the liquid falls below the vapour pressure of the fluid and sudden collapsing of these bubbles in the region of higher pressure.

In centrifugal pumps, the cavitation may occur at the inlet of the impeller of the pump or at the suction side of the pumps, where the pressure is considerably reduced.

Hence if the pressure at the suction side of the pump drops below the vapour pressure of the liquid then cavitation may occur.

QUESTION: 114

A bar held between two rigid supports will be subjected to tensile stress if it is

Solution:

When the temperature of the bar is raised, and the bar is not free to expand, the bar tries to expand and exerts axial pressure on the wall. At the same time wall puts equal and opposite pressure on the bar,, which will develop compressive stress in the bar.

If there is a drop in the temperature of the bar, the bar will try to contract, exerting a pull on the wall. At the same time, the wall offers equal and opposite reaction exerting a pull on the bar which will develop tensile stress in the bar.

Increase in temperature → Compressive stress

Decrease in temperature → Tensile stress

QUESTION: 115

In the case of the bi-axial state of normal stresses, the normal stress on 45° plane is equal to

Solution:

In the case of the bi-axial state of normal stresses:

Normal stress on an inclined plane:

Shear Stress on an inclined plane:

Normal stress on 45° plane:

QUESTION: 116

The angle between the line of stroke (line of motion of the follower) and the normal to the pitch curve at any point is referred to as

Solution:

The pressure angle, representing the steepness of the cam profile, is the angle between the normal to the pitch curve at a point and the direction of the follower motion. It varies in magnitude at all instants of the follower motion. A high value of the maximum pressure angle is not desired as it might jam the follower in the bearings.

QUESTION: 117

Two particles, each of mass m, collide head-on when their speeds are 2u and u. If they stick together on impact, find their combined speed in terms of u.

Solution:

Conservation of linear momentum:

m1u1 + m2u2 = (m1 + m2) V

m(2u) + m(-u) = (2m) V

mu = 2mV

V = u/2

QUESTION: 118

When inspection doors on the walls of boilers are opened, the flame does not leap out because

Solution:

The flame does not leap out during the opening of the inspection door because there is negative pressure in the combustion area. Negative pressure is achieved in balanced draft boilers by using forced draft fans to force air into the boiler (pressuring it) and Induced draft fans to remove air from the boilers to create negative pressure.

QUESTION: 119

A gas is compressed isothermally to half of its initial volume. The same gas is compressed separately through an adiabatic process until its volume is again reduced to half. Then

Solution:

The area under P-V diagrams represents the work done.

Since the slope of the adiabatic process is greater than the slope of the isothermal process.

On the P-V diagram, Area under adiabatic curve > Area under the isothermal curve.

Work done under an adiabatic process is greater than work done under an isothermal process.

QUESTION: 120

Two-stroke engines are used more frequently in two-wheelers due to which of the following reasons?

Solution:

Two-stroke engines often have a high power-to-weight ratio. Compared to four-stroke engines, two-stroke engines have a greatly reduced number of moving parts and so can be more compact and significantly lighter.

Important Point:

Two-stroke engines: In this engine, one power stroke is obtained in each revolution of the crankshaft

Four-stroke engines: In this type of engine, one power stroke is obtained in two revolutions of the crankshaft

QUESTION: 121

In an IC engine, the connecting rod connects which of the following pair of parts?

Solution:

In a reciprocating piston engine, the connecting rod connects the piston to the crank or crankshaft. Together with the crank, they form a simple mechanism that converts reciprocating motion into rotating motion.

In a reciprocating compressor or pump, connecting rods may also convert rotating motion into reciprocating motion.

QUESTION: 122

Which of the following instruments is used to measure flow on the application of Bernoulli’s theorem:

Solution:

The flow rate through a pipe is usually measured by providing a coaxial area contraction within the pipe and by recording the pressure drop across the contraction, which is the application of Bernoulli’s equation.

Three flow meters primarily operate on this principle:

- Venturimeter

- Orificemeter

- Pitot tube

QUESTION: 123

Power is transmitted by the lead screw to carriage through

Solution:

From the lead screw, the motion is transmitted to the carriage by engaging the half nut with the lead screw.

The cutting tool moves with the lathe carriage by the engagement of a half nut with the lead screw.

Acme threads are used in lathe lead screws. This form of thread enables the easy engagement of the half nut.

QUESTION: 124

If a prismatic bar be subjected to an axial tensile stress σ, then shear stress-induced on a plane inclined at θ with the axis will be

Solution:

Pn = The component of force P, normal to section FG = P cos θ

Pt = The component of force P, along the surface of the section FG (tangential to the surface FG) = P sin θ

σn = Normal Stress across the section FG

σn=σcos2θ

σt = Tangential/Shear Stress across the section FG

QUESTION: 125

Solution:

Nose radius: It is the curvature of the tooltip. It provides strengthening of the tool nose and a better surface finish. It is expressed in mm.

Proper tool nose radius improves machinability to some extent through an increase in tool life by increasing mechanical strength and reducing the temperature at the tooltip.

QUESTION: 126

The equation constant along a streamline holds true for

Solution:

PdA - (P + dP) dA - ρgdAds sin θ = 0

Assumptions in Bernoulli’s equation:

i) fluid is ideal

iii) flow is continuous

iv) fluid is incompressible

v) flow is non-viscous

vi) flow is irrotational

vii) applicable along a streamline

Where,

z = elevation of datum head

- The line representing the sum of all 3 head is known as the total energy line or total head line.

- Line joining the points of piezometric heads is known as hydraulic grade line or piezometric line.

QUESTION: 127

Which of the following statement is correct?

Solution:

Stress = force per unit area, i.e. F / A or N/m2

Strain = change in length per unit original length, i.e. m/m or mm/mm.

Hooke’s Law holds good up to the proportional limit.

According to Hooke’s Law, stress is directly proportional to strain within the elastic limit.

Note: Stress is not pressure per unit area because pressure itself is force per unit area.

QUESTION: 128

The design of thin cylindrical shells is based on

Solution:

The wall of a cylindrical shell subjected to internal pressure has to withstand tensile stresses of the following two types:

Circumferential or hoop stress, and (b) Longitudinal stress

Longitudinal stress:

Hoop stress:

We see that the longitudinal stress is half of the circumferential or hoop stress. Therefore, the design of a pressure vessel must be based on the maximum stress i.e., hoop stress.

QUESTION: 129

The purpose of reaming is

Solution:

Reaming removes a small amount of material from the surface of holes. It is done for two purposes:

1. To bring holes to a more exact size

2. To improve the finish of an existing hole

Important Point:

Boring: Boring is an operation to enlarging an existing hole, which may have been made by a drill or maybe the result of a core in a casting.

Drilling: Drilling is a cutting process that uses a drill bit to cut or enlarge a hole of circular cross-section in solid materials. The drill bit is a rotary cutting tool.

Reaming: Reaming is a sizing operation that removes a small amount of metal from a hole already drilled. It is done for two purposes: to bring holes to a more exact size and to improve the finish of an existing hole.

Mistake Point:

Drilling is used to enlarging the diameter. Reaming operation is meant to slightly increase the size and to provide a better tolerance and surface finish of an initially drilled hole.

QUESTION: 130

In the 3-2-1 principle of fixture design, 3 refers to the number of

Solution:

This is the principle to locate the workpiece firmly so that the required operations like drilling, reaming, etc. can be done.

According to the principle, 3 pins are used in primary datum, 2 pins are used on secondary datum, which is perpendicular to 1st, and 1 in tertiary datum, which arrests 9 degrees of freedom.

QUESTION: 131

A Carnot cycle refrigerator operates between 250 K and 300 K. Its coefficient of performance is

Solution:

QUESTION: 132

In the case of cam, the maximum value of the pressure angle is kept as-

Solution:

Pressure Angle is the measure of the steepness of the cam profile. The angle between the direction of the follower movement and the normal to the pitch curve at any point is called pressure angle. Pressure angle varies from maximum to minimum during complete rotation.

The pressure should not exceed 30 in the case of cams with translating followers (and angle should be less than 45for low-speed cam mechanisms with oscillating followers).

QUESTION: 133

One man takes 1 minute to raise a box to a height of 1 m, and another man takes ½ minute to do so. The energy of the two is

Solution:

Solution: Energy to lift a weight is calculated as:

E = mgh

Here height, h is the same for a box, so energy will be the same.

However, power is different as it is defined as the rate of energy to do work. Since the second man takes a shorter time for the same amount of work, he has greater power and does work faster.

QUESTION: 134

Which of the following is a positive clutch?

Solution:

The positive clutches are used when a positive drive is required. The simplest type of a positive clutch is a jaw or claw clutch or dog clutch.

Friction Clutches: The force of friction is used to start the driven shaft from rest and gradually brings it up to the proper speed without excessive slipping of the friction surfaces. Example: Disc or plate clutches, Cone clutches, Centrifugal clutches.

QUESTION: 135

In the case of power transmission through pipes, maximum efficiency is

Solution:

The efficiency of power transmission is given by

For maximum efficiency

We get

ηmax = 66.66%

QUESTION: 136

The dimensions of dynamic viscosity μ are

Solution:

The unit of dynamic viscosity is kg/(m.sec), and the dimension is ML-1T-1

QUESTION: 137

A liquid has surface tension σ. The minimum work required to divide a spherical drop of this liquid of radius t into 8 equal-sized spherical drops is

Solution:

The surface tension of a liquid is measured as the force acting per unit length on an imaginary line drawn tangentially on the free surface of the liquid.

Surface tension, S = Force/Length = F/L = Work done/Change in area

Work done in splitting a bigger drop (R) in ‘n’ smaller drops (r):

R3 = nr3 ⇒ r = n-1/3R

Here r = (8)-1/3t = 0.5 t

WD = 4πσ (nr2 – R2) = 4πσ (n(n-1/3R)2 – R2) = 4πσR2 (n1/3 – 1)

WD = 4πσt2 (81/3 – 1) = 4πσt2

QUESTION: 138

Viscosity is the most important property in the ______.

Solution:

- Viscosity is the most important property of lubricating oil. It is a measure of its internal friction or resistance to flow.

- It provides a measure of the thickness of lubricating oil at a given temperature; the higher the viscosity, the thicker the oil.

QUESTION: 139

For measuring flow by a Venturimeter, it should be installed in _______.

Solution:

- Venturimeter is a device that measures the flow rate of fluid through the pipe. It can be used in any position.

- When a venturimeter is placed in a pipe carrying the fluid whose flow rate is to be measured, a pressure drop occurs between the entrance and throat of the venturimeter.

- This pressure drop is measured using a differential pressure sensor and when calibrated, this pressure drop becomes a measure of flow rate.

QUESTION: 140

According to which law, all perfect gases change in volume by (1/273)th of their original volume at 0°C for every 1°C change in temperature when pressure remains constant

Solution:

temperature, when the absolute pressure remains constant, Mathematically,

Or “All perfect gases change in volume by (1/273)th of its original volume at 0°C for every 1°C change in temperature when the pressure remains constant."

Boyles law: The absolute pressure of a given mass of a perfect gas varies inversely as its volume when the temperature remains constant." Mathematically,

QUESTION: 141

Which of the following statements is not true for diamond?

Solution:

Diamond is one of the 8 allotropes of carbon.

Properties of a diamond:

1. It is the hardest known material.

2. Diamond is non - metallic.

3. It has high thermal conductivity, i.e., it is a good conductor of heat.

4. It has a very low electrical conductivity, i.e., it is a terrible conductor of electricity, or it does not conduct electricity at all, and it is used as an insulator also.

QUESTION: 142

In the figure shown below, the relative velocity of link 1 with respect to link 2 is 15 m/s. Link 2 rotates at a constant speed of 150 rpm. The magnitude of the Coriolis component of acceleration of link 1 is

Solution:

Concept:

When a point on one link is sliding along another rotating link, then the Coriolis component of the acceleration is to be calculated.

ac = 2 ωV

Where ω = Angular velocity of the link OA (rad/s) and v = Velocity of slider B with respect to the coincident point C (m/s)

Calculation:

Given: V = 15 m/s, ω = 150 rpm

QUESTION: 143

What is the number of instantaneous centres of rotation for a 6-link mechanism?

Solution:

The number of instantaneous centres in a constrained kinematic chain is equal to the number of possible combinations of two links.

The number of instantaneous centres:

where n is the number of links.

QUESTION: 144

Which of the following is a type of high-pressure boiler?

Solution:

Fire Tube Boiler: In this boiler, the hot flue gases are present inside the tubes, and water surrounds them. They are low-pressure boilers. The operating pressure is about 25 bar.

Example to fire tube boilers:

- Cornish boiler

- Cochran boiler

- Locomotive boiler

- Lancashire boiler

- Scottish marine boiler

Water Tube Boiler: In this boiler, water is present inside the tubes, and the hot flue gases surround them. They are high-pressure boilers. The operating pressure is about 250 bar.

Examples of water tube boilers:

- Stirling boiler

- Babcock and Wilcox boiler

- Yarrow boiler

- Lamont boiler

- Loeffler boiler

- Velox boiler

QUESTION: 145

The locus of elevations that water will rise in a series of the pitot tubes is called ______.

Solution:

- Within the piezometer tube, the locus of elevations to which the water would rise if open to the atmospheric pressure represent the Hydraulic grade line (HGL).

- The difference in elevation of the water surface in the successive conduit represents the friction and other minor losses in the conduits.

- If the conduit has a slope equal to the friction slope, then the HGL would be parallel to the conduit, ignoring minor losses.

- Energy grade line (EGL) = HGL + v2/2g

- The EGL will be represented by a series of pitot tubes (small tubes with their end openings pointed upstream) intercepting the kinetic energy of the flow.

QUESTION: 146

Which of the following statement is INCORRECT?

Solution:

- Intensive Property does not depend on the amount of matter; Example: Pressure, temperature

- Extensive property depends on the amount of matter. Example: Mass, Volume, Energy, etc.

- Intensive properties are independent of the mass in the system, while extensive properties are related to the mass; If the mass is increased, the value of the extensive properties also increases.

- Specific extensive properties i.e., specific volume, specific energy, etc. are intensive properties i.e., independent of the mass

QUESTION: 147

During an adiabatic process, the pressure of a gas is found to be proportional to the cube of its temperature. The ratio of for the gas is

Solution:

Concept:

P-V-T relationship for an adiabatic process:

QUESTION: 148

Identify the correct arrangement (in ascending order) of the hardness of structures of steel while undergoing a heat treatment process.

Solution:

Different phases of steel:

Ascending order of hardness:

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QUESTION: 149

The gear train usually employed in clocks is

Solution:

When the axes of the first gear and the last gear are co-axial, then the gear train is known as a reverted gear train. The reverted gear trains are used in automotive transmissions, lathe back gears, industrial speed reducers, and in clocks (where the minute and hour hand shafts are co-axial).

The epicyclic gear trains are useful for transmitting high-velocity ratios with gears of moderate size in a comparatively lesser space. The epicyclic gear trains are used in the back gear of lathe, differential gears of the automobiles, hoists, pulley blocks, wrist-watches, etc.

QUESTION: 150

A smooth cylinder lying on a convex surface remains in ________ equilibrium.

Solution:

- A body is said to be in equilibrium when it comes back to its original position after it is slightly displaced from its position of rest. In general, the following are the three types of equilibrium :

Stable equilibrium:

- A body is said to be in stable equilibrium if it returns back to its original position after it is slightly displaced from its position of rest

- This happens when some additional force sets up due to displacement and brings the body back to its original position

A smooth cylinder, lying on the curved surface, is in stable equilibrium

Unstable equilibrium

- A body is said to be in unstable equilibrium if it does not return back to its original position and heels farther away after slightly displaced from its position of rest

- This happens when the additional force moves the body away from its position of rest

- A smooth cylinder lying on a convex surface

Neutral equilibrium

- A body is said to be in neutral equilibrium if it occupies a new position (and remains at rest in this position) after slightly displaced from its position of rest

- This happens when no additional force sets up due to the displacement

- A smooth cylinder lying on a horizontal plane is in neutral equilibrium

QUESTION: 151

The manometer head (Hm) of a centrifugal pump is given by

Solution:

Suction Head (hs): It is the vertical height of the centre line of the centrifugal pump above the water surface in the tank or pump from which water is to be lifted.

Delivery head (hd): The vertical distance between the centre line of the pump and the water surface in the tank to which water is delivered is known as the delivery head.

Static Head (H): The sum of the suction head and the delivery head is known as the static head. H = hs + hd

Manometric Head (Hm): The manometric head is defined as the head against which a centrifugal pump has to work. It is given by the following expressions:

Hm = Head imparted by the impeller to the water – Loss of head in the pump

Hm = Total head at the outlet of the pump – Total head at the inlet of the pump

Hm = Suction Head (hs) + Delivery Head (hd) + Friction head loss in the suction pipe (hfs) + Friction head loss in the Delivery pipe (hfd) + Velocity head of water in the delivery pipe (V2/2g)

QUESTION: 152

Metacentre is the point of intersection of

Solution:

The point ' M ' at which the line of action of the new buoyant force intersects the original vertical through the CG of the body is called the metacentre. It is a point about which a floating body starts oscillating when given a small angular displacement.

Equilibrium Position Tilted Position

GM > 0 (M is above G) Stable equilibrium

GM = 0 (M coinciding with G) Neutral equilibrium

GM < 0="" (m="" is="" below="" g)="" unstable="" />

QUESTION: 153

The shear stress- shear strain rate graph for a Newtonian fluid is a

Solution:

Newtonian fluids are defined as fluids for which the shear stress is linearly proportional to the shear strain rate. Newtonian fluids are analogous to elastic solids (Hooke’s law: stress proportional to strain). Any common fluids, such as air and other gases, water, kerosene, gasoline, and other oil-based liquids, are Newtonian fluids.

Fluids for which the shear stress is not linearly related to the shear strain rate are called non- Newtonian fluids. Examples include slurries and colloidal suspensions, polymer solutions, blood, paste, and cake batter.

QUESTION: 154

The flow of water in a whirlpool of the river, is an example of

Solution:

In a free vortex flow, total mechanical energy remains constant. There is neither any energy interaction between an outside source and the flow nor is there any dissipation of mechanical energy within the flow. The fluid rotates by virtue of some rotation previously imparted to it or because of some internal action.

Some examples are a whirlpool in a river, the rotatory flow that often arises in a shallow vessel when liquid flows out through a hole in the bottom (when water flows out from a bathtub or a washbasin), and flow in a centrifugal pump case just outside the impeller.

QUESTION: 155

A Carnot heat engine is working with an efficiency of 50%. If the cycle is converted into a heat pump after reversing, then what is the coefficient of performance of the heat pump?

Solution:

The efficiency of Carnot engine (ηE) = 50%

ηE=1−TLTH=0.5

Now, this is converted to the heat pump,

Dividing by TH

Short trick:

If a Carnot heat engine which is operating between two temperature limits is converted to a heat pump, then

QUESTION: 156

A concentrated load P acts on a simply supported beam of span L at a distance L/4 from the left end. The bending moment at the point of application of load is given by:

Solution:

R1 + R2 = P

R2 × L = P × L/4

R2 = P/4

R1 = 3P/4

Bending moment at the point of applied load:

QUESTION: 157

The equivalent spring constant for a bar of length L, cross-sectional area A and modulus of elasticity E is subjected to an axial force P is

Solution:

Change in length of the bar:

δL = PL/AE

The ratio between the force and deflection is referred to as the spring rate or stiffness of the beam or coil.

Equivalent spring constant:

k = F/x = P/δL = AE/L

QUESTION: 158

A cylindrical elastic body subjected to pure torsion about its axis develops

Solution:

Pure torsion will be the case of pure shear in which principal normal stresses occur 45° to the axis.

Maximum and minimum principal stresses are equal in magnitude and opposite in direction.

1 = 90° ⇒ θ1 = 45°

QUESTION: 159

When a cast iron specimen is subjected to a tensile test, then percentage reduction in the area will be equal to

Solution:

In Brittle materials under tension test undergoes brittle fracture i.e. their failure plane is 90° to the axis of load, and there is no elongation in the rod that’s why the diameter remains the same before and after the load. Example: Cast Iron, concrete, etc.

But in the case of ductile materials, material first elongates and then fails, their failure plane is 45° to the axis of the load. After failure, cup-cone failure is seen. Example Mild steel, high tensile steel, etc.

QUESTION: 160

The purpose of normalizing is

Solution:

Normalizing: Heat the steel from 30°C to 50°C above its upper critical temp, held about fifteen minutes, and then allowed to cool down in still air. The homogeneous structure provides a higher yield point, ultimate tensile strength, and impact strength with lower ductility to steels.

Main objective

1. Refine grain size in metal, improve strength and hardness, reduce ductility

2. Remove cold worked stress.

3. Remove dislocations due to hot working.

QUESTION: 161

Which one of the following is a single-point cutting tool?

Solution:

Cutting tools may be classified according to the number of major cutting edges (points) involved as follows:

• Single point: e.g., turning tools, shaping, planning, and slotting tools (parting tool), and boring tools

• Double (two) point: e.g., drills

• Multipoint (more than two): e.g., milling cutters, broaching tools, hobs, gear shaping cutters, etc.

QUESTION: 162

What symbol is used to indicate surface roughness?

Solution:

indicates roughness.

The surface roughness on a drawing is represented by triangles.

Surface texture or roughness representation

The basic symbol consists of two legs of unequal length inclined at approximately 60° to the line representing the considered surface.

The symbol must be represented by a thin line.

The value of roughness is added to the symbols.

1. Roughness ‘a’ obtained by any production process

2. Roughness ‘a’ obtained by machining

3. Roughness ‘a’ obtained without removal of material

If it is necessary to impose maximum and minimum limits of surface roughness, both values are indicated. a1 = Maximum limit; a2 = Minimum limit

QUESTION: 163

Octane number of natural gas is

Solution:

The octane number of natural gas is around 110, which makes it a very good SI engine fuel. Because of this high octane number, the flame speed is higher and the engine can operate with a high compression ratio.

QUESTION: 164

Superheating in a refrigeration cycle

Solution:

Effect of Superheating:

1. Work input increases

2. Increase in refrigeration effect

3. COP may increase or decrease depending on the refrigerant; For e.g.,, in the case of Ammonia, superheating would result in a decrease of COP whereas, in the case of R-11, refrigerant superheating would result in an increase in COP.

QUESTION: 165

Sub-cooling in a vapour compression cycle

Solution:

Subcooling is the process of cooling the liquid refrigerant below the condensing temperature for a given pressure.

The difference between the saturation temperature and the temperature of a sub-cooled liquid at that pressure is called the Degree of subcooling.

Subcooling is beneficial as it increases the refrigeration effect by reducing the throttling loss at no additional specific work input.

Also, subcooling ensures that only liquid enters the throttling device leading to its efficient operation.

Effect of Subcooling:

- Increase the refrigeration effect

- Work input remains the same

- Increase in COP

QUESTION: 166

The maximum theoretical efficiency of the Pelton wheel is obtained when the ratio of bucket speed to jet-speed is

Solution:

The efficiency is maximum when the ratio of bucket speed to jet-speed is 0.5. Out of the given option, 0.46 is the most suitable one and near to maximum. The value of the speed ratio varies from 0.43 to 0.48.

QUESTION: 167

An orifice meter, having an orifice of diameter ‘d’ is fitted in a pipe of diameter D. For this orifice meter, what is the coefficient of discharge Cd?

Solution:

An orifice meter provides a simpler and cheaper arrangement for the measurement of flow through a pipe. An orifice meter is essentially a thin circular plate with a sharp-edged concentric circular hole in it.

Cd is defined as the ratio of the actual flow and the ideal flow and is always less than one.

For the orifice meter, the coefficient of discharge Cd depends on the shape of the nozzle, the ratio of pipe to nozzle diameter, and the Reynolds number of the flow.

QUESTION: 168

A hydraulic coupling

Solution:

The fluid or hydraulic coupling is a device used for transmitting power from the driving shaft to the driven shaft, running at a different speed with the help of fluid. There is no mechanical connection between the shafts.

QUESTION: 169

Heat is closely related with

Solution:

Actually, there is a distinct difference between heat and temperature.

Temperature is a measure of the amount of energy possessed by the molecules of a substance. It manifests itself as a degree of hotness and can be used to predict the direction of heat transfer. The usual symbol for temperature is T. The scales for measuring temperature in SI units are the Celsius and Kelvin temperature scales.

Heat, on the other hand, is energy in transit. Spontaneously, heat flows from a hotter body (higher temperature) to a colder one (lower temperature). The usual symbol for heat is Q. In the SI system, common units for measuring heat are the Joule and calorie.

Confusion point:

There are different types of energy. Heat is a transfer of thermal energy.

The driving force for heat transfer is the temperature difference.

QUESTION: 170

If r = chip thickness ratio, α = rake angle, then shear angle ϕ is expressed as

Solution:

In machining process,

Chip thickness ratio (r) = chip;thickness(t2)}

where, φ = shear angle, α = rake angle

the uncut chip thickness value is less than the chip thickness value; thus chip thickness ratio is less than 1.

QUESTION: 171

At 100% relative humidity, the wet-bulb temperature is:

Solution:

When the relative humidity of the air is 100%, i.e, the air is saturated, the dew point temperature (DPT) equals the wet-bulb temperature (WBT), which is also equal to the dry-bulb temperature.

So DBT = WBT = DPT

For unsaturated air:

DBT > WBT > DPT

QUESTION: 172

The air standard Otto cycle consists of

Solution:

Air standard Otto cycle consists of two constant volume and two isentropic processes.

Process 1–2: An adiabatic (isentropic) compression

Process 2–3: A constant-volume heat addition

Process 3–4: An Adiabatic (isentropic) expansion

Process 4–1: A constant-volume heat rejection

QUESTION: 173

Which one of the following is a higher pair?

Solution:

Lower pair: When the two elements of a pair have a surface contact when relative motion takes place, and the surface of one element slides over the surface of the other, the pair formed is known as the lower pair. Sliding pairs, turning pairs, and screw pairs are examples of lower pairs.

Higher pair: When the two elements of a pair have a line or point contact when relative motion takes place, and the motion between the two elements is partly turning and partly sliding, then the pair is known as higher pair. A pair of toothed gearing, belt and rope drives, ball and roller bearings, and cam and follower are examples of higher pairs.

In Belt and pulley, due to line contact, they form a higher pair.

QUESTION: 174

Which of the following is a boiler mounting?

Solution:

Boiler accessories are those components that are installed either inside or outside the boiler to increase the efficiency of the plant and to help in the proper working of the plant.

Various boiler accessories are:

1) Air Preheater

2) Economizer

3) Super-heater

4) Feed Pump

5) Injector

Boiler mountings are the machine components that are mounted over the body of the boiler itself for the safety of the boiler and for complete control of the process of steam generation.

Various boiler mountings are as under:

1) Pressure gauge

2) Water Level Indicator

3) Fusible plug

4) Safety Valve

i) Lever Safety Valve

5) Steam stop valve

6) Feed check valve

7) Blow off cock

QUESTION: 175

An increase in pressure of a liquid from 7.5 MPa to 15 MPa results in a 0.2 percent decrease in its volume. The coefficient of compressibility of the liquid in m2/N is

Solution:

dV = 0.2%

Compressibility (β) =

QUESTION: 176

When a process undergoes a complete cycle, then the change of entropy will be

Solution:

Since entropy is a point function that depends only on states i.e., independent of the path followed.

So the change of entropy will be zero when the process undergoes a complete cycle (where the initial state and final state are the same).

QUESTION: 177

Electrode used in TIG is :

Solution:

Introduction of TIG Welding

Gas Tungsten Arc Welding (GTAW), also known as tungsten inert gas (TIG) welding, is a process that produces an electric arc maintained between a non-consumable tungsten electrode and the part to be welded.

Inert Gas in TIG Welding

The heat-affected zone, the molten metal, and the tungsten electrode are all shielded from atmospheric contamination by a blanket of inert gas fed through the GTAW torch.

Inert gas is inactive or deficient inactive chemical properties. The shielding gas serves to blanket the weld and excludes the active properties in the surrounding air. Inert gases, such as Argon and Helium, do not chemically react or combine with other gases.

QUESTION: 178

Two vapour power cycles having efficiencies of 0.5 and 0.6 are coupled in series, then the efficiency of the coupled cycle will be ____

Solution:

For two coupled cycle in series

η=1−(1−η1)(1−η2)

=1−[1−η1−η2+η1⋅η2]

12−η1⋅η2

= 0.5 + 0.6 – 0.5 × 0.6 = 0.80

QUESTION: 179

The hydrostatic law states that rate of increase of pressure in a vertical direction

Solution:

The pressure at any point in a fluid at rest is obtained by the Hydrostatic Law, which states that the rate of increase of pressure in a vertically downward direction must be equal to the specific weight of the fluid at that point.

P = ρgh

QUESTION: 180

In Kaplan turbine runner, the number of blades is generally of the order _____.

Solution:

Kaplan turbine has adjustable runner blades. Kaplan Turbine has a very small number of blades, 3 to 8. Francis Turbine has a very large number of blades, 16 to 24.

QUESTION: 181

The curl of a given velocity field (∇ x -V) indicates the rate of

Solution:

The curl indicates the rate of deformation.

The angular velocity vector is defined as:

The vorticity of a flow field is defined as:

Rate of rotation of fluid element ABCD about the ?-axis is defined as the average of the angular speeds of two mutually perpendicular lines AB (dx element) and AD (dy element):

QUESTION: 182

Double hemispherical buckets are used in

Solution:

The Pelton wheel or Pelton turbine is a tangential flow impulse turbine. The water strikes the bucket along the tangent of the runner. The shape of the buckets is of double hemispherical cup or bowl. Each bucket is divided into two symmetrical parts by a dividing wall known as a splitter. The jet of water strikes on the splitter. The splitter divides the jet into two equal parts, and the jet comes out at the outer edge of the bucket. The buckets are shaped so that the jets get deflected through 160 ° or 170 °.

QUESTION: 183

Rankine's theory is applicable to which type of materials

Solution:

Rankine's Theory assumes that failure will occur when the maximum principal stress at any point reaches a value equal to the tensile stress in a simple tension specimen at failure.

This theory does not take into account the effect of the other two principal stresses. Rankine's theory is satisfactory for brittle materials and not applicable to ductile materials.

This theory is also called the Maximum Stress Theory.

QUESTION: 184

In a thermodynamic system, thermal equilibrium is achieved when two bodies reach

Solution:

A mechanical equilibrium exists when all the mechanical forces within a system are balanced so that there is no acceleration.

A thermal equilibrium exists within a system when the temperature is uniform throughout so that there is no heat transfer within the system.

A phase equilibrium exists within a system when there are no phase transformations, such as melting, vaporization, etc., within the system.

A chemical equilibrium exists when there are no chemical reactions within the system.

QUESTION: 185

The process of improving the cutting action of the grinding wheel is called

Solution:

When the sharpness of the grinding wheel becomes dull because of glazing and loading, dulled grains and chips are removed (crushed or fallen) with a proper dressing tool to make sharp cutting edges.

A dressing is the conditioning of the wheel surface, which ensures that grit cutting edges are exposed from the bond and can penetrate the workpiece material. Also, in dressing, attempts are made to splinter the abrasive grains to make them sharp and free cutting and to remove any residue left by the material being ground. Dressing, therefore, produces micro-geometry.

The purpose of dressing is to restore the correct cutting action of the wheel.

QUESTION: 186

In arc welding, eyes need to be protected against

Solution:

Welding arcs give off radiation over a broad range of wavelengths - from 200 nm (nanometers) to 1,400 nm (or 0.2 to 1.4 µm, micrometers).

This includes ultraviolet (UV) radiation (200 to 400 nm), visible light (400 to 700 nm), and infrared (IR) radiation (700 to 1,400 nm).

This is the reason that eyes need to be protected against both UV and Infra-Red rays.

QUESTION: 187