HPCL Electrical Engineer Mock Test - 3 - PSSSB Clerk MCQ

Calculation:

Total principal = 25000 and total interest receive = 2031.25

So, all-over interest rate = 2031.25/25000 × 100 = 8.125%

So, the 1st part and 2nd part of the principal were lent out in the ratio 3 : 1

Now, the 2nd part of the money is = 25000 × = Rs. 6250

∴ The correct answer is Rs. 6,250

Given:

Diameter = 84 cm

Length = 1 m

Formula used:

Curved surface area of cylinder = 2πrh

Calculation:

According to question,

⇒ 2πrh = 2 × 22/7 × 42 × 100

⇒ 2 × 22 × 6 × 100

Area of the road being levelled = 750 × 2 × 22 × 6 × 100

⇒ 19800000 = 1980 m²

∴ The correct answer is 1980 m².

Given

Time taken by A, B, and C to complete one round: 6 min, 8 min, 3 min respectively

Concept:

The time they will meet again at the starting point will be the least common multiple (LCM) of their individual times.

Solution:

LCM of 6, 8, and 3 minutes = 24 minutes

They started at 5:00 p.m. so they will meet again at 5:00 p.m. + 24 minutes ⇒ 5:24 p.m.

Therefore, they will meet again at the starting point at 5:24 p.m.

The given statement is: D > B ≥ W, Y > W > M

Combine the statement: D > B ≥ W, Y > W > M

Conclusions:

I. B ≥ M → False (as D > B ≥ W, Y > W > M gives; as B ≥ W > M; so B > M).

II. M < D → True (as D > B ≥ W, Y > W > M gives; as D > B ≥ W > M; so M < D).

Hence, the correct answer is “Only conclusion II is true”.

Given: A B C D E F G H I J K L M N O P R S T U V W X Y Z

Logic: The letter which is fifth to the left from the thirteenth letter from your right.

The 13th from the right is 'M'.

The 5th letter to the left from the thirteenth letter from right (Which is M) is 'H'.

So, H will be the answer.

Hence, the correct answer is "Option 1".

The words given are different planetary bodies arranged in increasing order of their size.

3. Moon (Smallest among all).

4. Earth (Bigger than moon).

2. Sun (Bigger than Earth).

5. Stars (Bigger than Sun).

1. Milky-way (Biggest among all).

Hence, The correct answer is "Option 1".

Key Points

• The phrase "unless they are hungry" correctly completes the sentence by providing a condition that must not be met for the action (attack) to occur.
• The word 'unless' introduces a conditional clause, indicating that the action mentioned (tigers attacking) will not happen unless the condition (being hungry) is fulfilled.
• The use of 'unless' implies a specific condition that contradicts the main clause, making it the most appropriate choice for the blank.
• Other options like 'because', 'if', and 'although' do not correctly convey the intended meaning of the sentence, which is about a condition preventing an action unless it is met.

Hence, the correct answer is option 3.

Correct sentence: Tigers won't attack unless they are hungry.

Additional Information

• Because is used to give a reason for something, which does not fit the conditional nature of the sentence.
• If introduces a condition but lacks the exclusive context that 'unless' provides, suggesting that the action might happen under other conditions as well.
• Although introduces a contrast or exception, which does not align with the conditional requirement of the sentence.

Given statements:

M ≥ Z ≥ B > R < T ≤ V

Conclusions:

I. M > B → False (no definite relation is given between M and V)

II. R < V → True (no definite relation is given between R and V)

III. M = B → False (it is possible but not definite)

M ≥ B is True,

Hence, Only II follow and Either I or III follow is the correct answer.

1. R, N, O, W, Q and C are sitting around a circular table facing the center.

2. R is sitting to the immediate left of W, who is facing O, O is sitting to the immediate left of N.

3. C is not an immediate neighbor of W.

The final arrangement will be as shown below:

W is sitting to the left of Q.

Hence, ‘W’ is the correct answer.

Preparing the family tree using the following symbols:

Possible tree diagram will be

Hence, Jd is Cousin of Bd.

We would use the concept of BODMAS-

Calculation:

60 ÷ 16 × 2 - [76 ÷ 5 of 19 - 15 ÷ 8 × (21 - 25) - 3] ÷ 53

⇒ 60 ÷ 16 × 2 - [76 ÷ 5 of 19 - 15 ÷ 8 × -4 - 3] ÷ 53

⇒ 60 ÷ 16 × 2 - [76 ÷ 95 - 15 ÷ 8 × -4 - 3] ÷ 53

⇒ 60 ÷ 16 × 2 - [ -  × -4 - 3] ÷ 53

⇒ 60 ÷ 16 × 2 - [ +  - 3] ÷ 53

⇒ 60 ÷ 16 × 2 - [ - 3] ÷ 53

⇒ 60 ÷ 16 × 2 - [] ÷ 53

⇒ 60 ÷ 16 × 2 - [] ÷ 53

⇒  × 2 - 

⇒  - 

⇒  = 

∴ The answer is .

Given,

Area of the floor of rectangular hall = 500 m²

Formula:

Area of the rectangle = length × breadth

Calculation:

Let length of the rectangular hall be 5x

Breadth of the rectangular hall = 5x × (4/5) = 4x

According to the question

5x × 4x = 500

⇒ 20x² = 500

⇒ x² = 500/20

⇒ x² = 25

⇒ x = 5

The correct answer is "ejected; evacuate."

Key Points

• "Ejected" - This is the past tense of the verb "eject", which means to discharge or expel something, in this case, a large amount of ash from the volcano.
• The phrase "Without warning" implies a sudden or unexpected event that happened in the past, and so, the past tense verb "ejected" is the most contextually appropriate form.
• It clearly communicates that this happened as a single event in the past.
• "Evacuate" - This verb means to move people from a dangerous place to a safe place.
• In the sentence, it is preceded by "to," which requires the base form of a verb.
• As "force" implies a need for an action as response to a situation, "evacuate" fits perfectly to denote the action that residents were required to take as a direct result of the ash eruption from the volcano.

Therefore, the correct answer is "Option 3."

Given:

Ratio of height and radius of cylinder 3 : 2

Volume of cylinder = 12000π

Formula:

Volume of cylinder = πr²h

Calculation:

Ratio of height and radius of cylinder = 3 : 2 = 3x : 2x

According to the question

π × (2x)² × 3x = 12000π

⇒ 4x² × 3x = 12000

⇒ x³ = 12000/12

⇒ x = ∛1000

⇒ x = 10

Given:

A and B can do a piece of work in 15 days, while B and C can do the same work in 12 days, and C and A in 10 days.

They all work together for 5 days, and then B and C leave.

Concept used:

Total Work = Work done each day × Total time taken (in days)

Calculation:

LCM (15, 12, 10) = 60

Let the total work be the LCM of the time taken by them.

Hence, total work = 60 units

Thus,

A & B together do each day = 60 ÷ 15 = 4 units

B & C together do each day = 60 ÷ 12 = 5 units

C & A together do each day = 60 ÷ 10 = 6 units

Hence,

A + B = 4 ....(1)

B + C = 5 ....(2)

C + A = 6 ....(3)

Now, 2(A + B + C) = 15 ....(4)

Solving these equations we get,

A = 2.5; B = 1.5; C = 3.5.

Now, in 5 days work done = 5 × (A + B + C) = 5 × 7.5 = 37.5 units

Remaining work = 60 - 37.5 = 22.5 work

Time taken by A to complete the work = 22.5 ÷ 2.5 = 9 days

∴ Time taken by A to complete the work is 9 days.

Inital position of A is 13th from the right side but after shifting him third to the left A is at 16th position from the right.

Position from left = total person - Position from the right + 1

Position from left = 26 -16 + 1 = 11th

Hence, Option (3) is correct.

Given:

Six Friends: Falak, Charu, Sargun, Karan, Arav and Vaibhav

1.Falak is third to the right of Charu.

2. Charu is at the North end of the bench.

3.Arav is sitting to the immediate left of Falak.

4.Vaibhav and Karan are sitting immediately next to each other.

5.There are only two people sitting between Sargun and Karan.

so case 1.1, 2.1 and 2.2 gets cancelled.

Hence. Karan is the correct answer.

Given statement:

M ≥ Z ≥ B > R < T ≤ V

Conclusions:

I. M > R → True (M ≥ Z ≥ B > R)

II. R < V → True (R < T ≤ V)

Hence, Both I and II follow is the correct answer.

Concept:

The voltmeter sensitivity (S_v) is determined by dividing the sum of the resistance of the meter (Rm)

Mathematically, sensitivity is expressed as:

E = Rated Voltage or Full scale Reading

Voltmeter sensitivity is expressed in Ohm/Volt

R_m = S_v × E

Calculation:

Sensitivity of voltmeter = 500 Ω/V

Internal resistance of voltmeter = 500 × 20 = 10 kΩ

Effective resistance across A – B is

= 10 || 15 = 6 kΩ

The voltmeter reading is 10 V

⇒ VAB = 10 V

By voltage division,

⇒ Vs = 60 V

Concept:

Induction and Method of Images:

• When a charge Q is brought near a conductor surface, the radially outward field has tangential components at the conductor. This displaces the free electrons that are accumulated as an induced surface charge.
• These displaced electrons create a counterforce and hence the final tangential component of the Electric field is zero.
• The resultant field has only normal components and appears to be a dipole’s field with an image charge below the conductor surface at the same distance as shown below:

Application:

The force between two point charges is given by:

Here Q⁺ = Q^- = 2 C and d = 1 m

∴ r = 2d = 2 m

Note: The direction will be towards the plane.

Concept:

Transmission or ABCD parameters

General two-port network and Transmission parameters two-port network is shown below.

Transmission 2 port network

The direction of I2 is opposite to the standard form so it is taken as negative.

Transmission parameters are defined as:

V1 and I1 are dependent and V2 and I2 are independent.

Calculation:

From the ABCD parameters matrix, we get the following equations.

V1 = A V2 – B I2 ---(1)

I1 = C V2 - D I2 ---(2)

To calculate C, we open circuit the output terminal as shown:

Using Equation (1), we get:

I1 = C V2

Since I₂ = 0, the current across Z_b will be I₁, i.e.

V₂ = I₁ × Z_b

Concept:

According to Mason’s gain formula, the transfer function is given by

Where, n = No of forward paths

Mk = kth forward path gain

Δk = the value of Δ which is not touching the kth forward path

Δ = 1 – (sum of the loop gains) + (sum of the gain product of two non-touching loops) – (sum of the gain product of three non-touching loops)

Application:

Given signal flow graph is

Forward paths

M₁ = s × s × 1/s = s

M₂ = 1/s × 1/s = 1/s²

Loops:

L₁ = s × s (-1) = - s²

L₂ = -1/s

L₃ = s × s × 1/s × (-s) = -s²

L₄= 1/s × 1/s × (-s) = - 1/s

Δ = 1 - ( - s2 - s2 - 1/s - 1/s) = 1 + 2s² + 2/s

The Correct answer if option (2)

Concept:

Protective Relay:

• Pick-up value is the minimum relay operating coil current above which the relay starts its operation.
• If the relay operating coil current is less than the pick-up value relay does not operate.
• If both are equal, relay is on the threshold.

The current setting is defined as the ratio of the pick-up value of the relay to the relay current rating.

The current setting is also expressed in amperes, in Amperes Current setting is equal to the pick-up value.

Plug setting Multiplier (PSM):

PSM = Primary current of CT / (CT ratio × Relay current setting (A) (or)

PSM = (secondary fault current) / (Relay current setting (A) or pick-up current)

Calculation:

Given that,

Pick up current = Relay current setting (A) = 7.5 A

Fault current = 30 A

PSM = (30 / 7.5) = 4

The relationship between the impedance and admittance is given by:

where Z = Impedance

Y = Admittance

The impedance is analogous to admittance in the following ways:

ZPF or Potier triangle method:

• This method depends on the separation of the leakage reactance of armature and its effects.
• It is used to obtain the leakage reactance and field current equivalent of armature reaction.
• It is also called a general method of voltage regulation.
• It is the most accurate method of voltage regulation.
• For calculating the regulation, it requires open circuit characteristics and zero power factor characteristics.

​

The following assumptions are made in this method.

• The armature resistance is neglected.
• The O.C.C taken on no-load accurately represents the relation between MMF and voltage on load.
• The leakage reactance voltage is independent of excitation.
• The armature reaction MMF is constant.

Concept:

The nature of the control system is defined on the basis of the value of the damping ratio.

A two-port network is said to be symmetrical if the input and output ports can be interchanged without altering the port voltages and currents.

A network is said to be reciprocal if the ratio of the response to the excitation is invariant to an interchange of the positions of the excitation and response of the network.

Conditions of reciprocity and symmetry in terms of different two-port parameters are:

Concept:

Gauss Law states that the net electric flux through a closed surface enclosing a volume equals the charge enclosed by it.

Since D = ϵ0 E, we can write:

D̅ is the electric flux density.

Analysis:

We construct a Gaussian surface at ρ = r as shown in the figure:

So, according to Gauss law, the total outward flux through the surface ρ = r will be equal to the charge enclosed by it.

Assuming the height of the cylinder to be ‘h’, we can write:

D(2πrh) = ρ_v (πr²h)

Therefore the electric field intensity at a distance r from the cylindrical axis will be:

Thus E ∝ r

A. Thyristor – Slow device

B. MOSFET - Large on-state drop, no secondary breakdown

C. IGBT – Low on state drop

D. BJT - Low on state drop, secondary breakdown

Additional Information

Power MOSFET:

• Power MOSFET has lower switching losses but its on-resistance and conduction losses are more.
• MOSFET is a voltage-controlled device whereas BJT is a current controlled device.
• MOSFET has positive temperature coefficient for resistance. This makes parallel operation of MOSFETs easy. If a MOSFET shares increased current initially, it heats up faster, its resistance rises, and this increased resistance causes this current to shift to other devices in parallel.
• In MOSFET, secondary breakdown does not occur, because it has positive temperature coefficient.

BJT:

• A BJT has higher switching losses but lower conduction losses.
• A BJT has negative temperature coefficient, so current-sharing resistors are necessary during parallel operation of BJTs.
• As BJT has negative temperature coefficient, secondary breakdown occurs. With decrease in resistance, the current increases. This increased current over the same area results in hot spots and breakdown of the BJT.

Insulated Gate Bipolar Transistor (IGBT): It is a three-terminal power semiconductor device primarily used as an electronic switch. It is a 4 layer PNPN device that combines an insulated gate N-channel MOSFET input with a PNP BJT output in a type of Darlington configuration.

​Insulated gate Bipolar Transistor is also known as Conductivity-Modulated Field Effect Transistor.

Advantages:

• The insulated gate bipolar transistor (IGBT) is easy to turn ON and OFF.
• The switching frequency is higher than that of power BJT.
• It has a low on state power dissipation.
• It has simpler driver circuit.

Disadvantages:

• The switching frequency of insulated gate bipolar transistor (IGBT) is not as high as that of a power MOSFET.
• High turn-off time
• It cannot block high reverse voltages.

Y parameter:

I₁ = V₁ Y₁₁ + V₂ Y₁₂

I₂ = V₁ Y₂₁ + V₂ Y₂₂

 ...1)

 ...2)

Calculation:

For the given question Z = 5 Ω