HPCL Mechanical Engineer Mock Test - 8 - Mechanical Engineering MCQ

We can say that ,
The above given sentence is given in Passive Voice :-
Use structure “subject + auxiliary + past participle + by + object”
The beggar was laughed at by the boy.
Thus , option B will be required answer .

The original sentence is in the active voice: "Do not disturb the patient."

The best expression of this sentence in the passive voice is: "The patient is not to be disturbed."

Therefore, the correct answer is indeed option B: "The patient is not to be disturbed."

Since, 5 and 8 are the remainders of 70 and 125, respectively. Thus, after subtracting these remainders from the numbers, we have the numbers 65 = (70-5),
117 = (125 – 8), which is divisible by the required number.
Now, required number = HCF of 65,117                                     [for the largest number]
For this, 117 = 65 × 1 + 52 [∵ dividend = divisior × quotient + remainder]
⇒ 65 = 52 × 1 + 13
⇒ 52 = 13 × 4 + 0
∴ HCF = 13 
Hence, 13 is the largest number which divides 70 and 125, leaving remainders 5 amnd 8.

Hence, Option A is correct.

Hence, Option C is correct.

Hence, Option A is correct.

From the common explanation, we get the immediate neighbour of P and U is S.
Hence, Option D is correct.
Final Arrangement:

Common Explanation:
References:
Exactly two persons are sitting between P and Q.
Only one person is sitting between P and U.
Inferences:
From the above references, we get two different cases:

References:
S is sitting second to the right of R.
Inferences:
From the above reference, we get the following arrangements:

References:
T is not sitting beside S.
Inferences:
So, from this case 2 will be eliminated as T is not sitting beside S.
Hence, we get our final arrangement:

The numeric value of the letters (considering A to be 1 and Z to be 26) is added and simplified to obtain a single digit.
For ZOO, the numeric value of Z, O and O is 26, 15 and 15 respectively. Their sum is 56, Now 56 is further simplified to obtain a single digit by adding 5 and 6, which gives us 11 which is again added to obtain 2 as the final value.
Similarly for TAN, the numeric value of T, A and N is 20, 1 and 14 respectively. Their sum is 35, which is simplified as 3 + 5 = 8.
Similar process will be done to obtain the code for WAR, the numeric value of W, A and R is 23, 1 and 18 respectively. Their sum is 42, which is simplified as 4 + 2 = 6.
So, the code for WAR is 6.
Hence option (B) is correct.

∴ STOLL → $2@33
Hence, option B is correct.

The logic follows here is:

Middle number = square root of first number + third number.

Row-wise operation :

(25, 41, 36)

middle number = 41

= √25 + 36

= 5 + 36

= 41

(49, 45, 38)

middle number = 45

= √49 + 38

= 7 + 38

= 45

Similarly

(36, ?, 62)

middle number = ?

= √36 + 62

= 6 + 62

= 68

Hence, the correct answer is "68"

Additional Information

The most common pattern asked in exams are based on:

• It could be the sum of two numbers divided by a constant
• It could be the average of numbers.
• It could be in the form of alphabets, where alphabets are increased by constant or increased by the square of numbers or increased by prime numbers.
• It could be the difference of product of two diametrically opposite numbers.
• It could be the difference in the sum of adjacent numbers.
• The difference of the numbers could be in the patterns 13 ± 1, 23 ± 1,  and so on.
• The difference of the numbers could be in the patterns 12 ± 1, 22 ± 1, and so on.
• Numbers could be 12, 22, 32, and so on or 13, 23, 33, and so on.
• The difference could be prime numbers or the difference could be the square of prime numbers.
• The difference could be in the form of N2 ± N or N3 ± N.
• The difference could be in the form of ×N + N or ×2 + 1, ×2 + 2, ×2 + 3, and so on.
• The difference could be in the form of ×2 ± 1 alternatively.
• Numbers could be ×1, ×2, ×3, and so on. 

If you fold the paper in upward direction from dotted line, the upper line of the figure will be near to middle line. So it will make s triangle. Please take a transparent paper and draw a similar figure and fold it.

Gas Constant = R/M

⇒ R = Gas constant × Molecular weight.

If two or more shaft of different material, diameter or basic forms are connected together in such a way that each carries the same torque, then the shafts are said to be connected in series.

Lise Meitner

December 1938: Discovery of Nuclear Fission. In December 1938, over Christmas vacation, physicists Lise Meitner and Otto Frisch made a startling discovery that would immediately revolutionize nuclear physics and lead to the atomic bomb.

• Stable equilibrium : GM > 0 (M is above G) i.e. Metacentric height is positive.
• Neutral equilibrium : GM = 0 (M coinciding with G)
• Unstable equilibrium : GM < 0="" (m="" is="" below="" g)="" />

Condition of stable equilibrium for a submerged body in terms of centre of buoyancy and the centre of gravity:

• Stable equilibrium: If its centre of gravity is directly below the centre of buoyancy
• Neutral equilibrium: If its centre of gravity is coincident with the centre of buoyancy
• Unstable equilibrium: If its centre of gravity is directly above the centre of buoyancy

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.

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

The “typical” reciprocating compressor is used for discharge pressures up to 12,000 psi (828 bar). Special compressors (called hyper compressors) are used in low-density polyethylene production and discharge at pressures up to 50,000 psi (3500 bar).

P= Pitch

d= depth of thread

r= radius at crest and root

Example of firing tube boilers:

• Cornish boiler

• Cochran boiler

• Locomotive boiler

• Lancashire boiler

• Scotch 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, and the operating pressure is about 250 bar.

• Stirling boiler

• Babcock and Wilcox boiler

• Yarrow boiler

• Lamont boiler

• Loeffler boiler

Ignition quality of petrol is expressed by octane number and that of diesel by cetane number.

The equilibrium of a body submerged in a liquid requires that the weight of the body acting through its centre of gravity should be collinear with an equal hydrostatic lift acting through the centre of buoyancy.

• Stable Equilibrium: If the body returns to its original position by retaining the originally vertical axis as vertical
• Unstable Equilibrium: If the body does not return to its original position but moves further from it
• Neutral Equilibrium: If the body neither returns to its original position nor increases its displacement further, it will simply adopt its new position

The relative position of the centre of gravity (G) and centre of buoyancy (B) of a body determines the stability of a submerged body.

• Stable Equilibrium: B is above G

• Unstable Equilibrium: B is below G

• Neutral Equilibrium: B coincides with G

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.

2θ₁ = 90° ⇒ θ₁ = 45°

Correct Answer :- D

Explanation : The process of preheating involves heating the area around the weld joint or the entire part to a specified temperature before welding. This reduces the cooling rate of the weld and drives out moisture, which in turn helps prevent hydrogen buildup and the potential for cracking.

Refrigerating effect = h₁−h₄

Work input = h₂−h₁