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Electrical Engineering MCQs

Electrical Engineering MCQs helps to pass the initial tests of Army Lady Officers who want to join Pak Army through Lady Cadet Corps, Engineering Branch of PAF or Naval Commission.

If you have degree in Electrical Engineering then you may study all questions given below which are very helpful as past experience or past papers of LCC and other initial tests of PAF and Navy.

Electrical Engineering MCQs PDF

Electrical Engineering MCQs (Part-01)

Which of the given motor has insufficient starting torque at full load speed with the same H.P. ratings?

1. Three-phase Induction motor
2. Shunt motor
3. Synchronous motor
4. Differential compound motor

Which of the given networks are based on the compensation theorem?

1. Unilateral network
2. Bilateral network
3. Linear and non-linear network
4. Distributed network

The ratio of the Mechanical Impedance is

1. RMS force to RMS displacement
2. RMS velocity to RMS acceleration
3. RMS force to RMS velocity
4. RMS current to RMS speed

In a two-wattmeter method, the measured power was 40kW At 0.8 lagging power factor. Calculate the reading of each wattmeter

1. W1= 34.875 and W2 = 5.125
2. W1= 33.875 and W2 = 6.125
3. W1 = 38.875 and W2 = 6.125
4. W1 = 32.875 and W2 = 5.125

Under no-load conditions, the transmission line carrying a current because of

1. Heating effect
2. Capacitance effect
3. Chemical effect
4. Transmission effect

In a synchronous machine, the V curve is drawn between which of the given axis.

1. Field current on X-axis and no-load current on Y-axis
2. Armature current on X-axis and the no-load current in Y-axis
3. Field current on X-axis and armature current on Y-axis
4. Armature current on X-axis and filed current on Y-axis

The spot welding is used for

1. Joint thick sheets
2. Rough surface
3. Thin metal sheets(10-12mm)
4. T shape welding

In a 3-Ø induction motor, the starting current is 8 times the rated current, and the rated slip is 6 %, then find the ratio of starting torque to full load torque.

1. 1
2. 1.5
3. 1.75
4. 2

The single-phase reluctance machine works as a generator when the value of ? is

1. Infinitive
2. Zero
3. Unity
4. Positive

In a series circuit, the value of resistance is 40 ohm, and Inductance is 40mH . If the 100V of an A.C. source is connected to the circuit with 80Hz Frequency, find the value of current flowing through the resistance.

1. 23 A
2. 2.23 A
3. 3.33 A
4. 4.33 A

The Primary reason for D.C. motor Preferred over A.C. motor

1. Constant speed operation
2. High-speed operation
3. Variable speed operation
4. Low-speed operation

If the five bulbs having power ratings 5W,10W,25W,35W, and 50W, which one will have the highest resistance?

1. 5W bulb
2. 50W bulb
3. 25W bulb
4. 10W bulb

If the number of turns 4 times and length becomes double in a solenoid, and keeping the cross-sectional area are same, then find the ratio of Inductance (Older to newer).

1. 2
2. 4
3. 6
4. 8

Electrical Engineering MCQs Book

Electrical Engineering MCQs (Part-02)

Find the term ratio of the bridge rectifier at 20V D.C. output when the supply voltage is 230V, 50Hz.

1. 10:1
2. 20:1
3. 1:15
4. 1:13

In the given 8085 microprocessor, the restart instruction(RST) is 8 instruction. What would be the transfer program execution to a given location?

1. (0020)H
2. (0030)H
3. (0040)H
4. (0010)H

The purpose of dummy coil in D.C. machine is

1. to reduce losses
2. to Improve machine efficiency
3. to maintain a mechanical balance of armature
4. to reduce the cost of the machine

The load factor of a plant is 0.8, and the capacity factor is 0.7. If the maximum demand on the plant is 600 MW, find the reserve capacity of the plan

1. 25
2. 85
3. 105
4. 120

A bulb of power rating 9kW draws a current 30 A. Find the applied Voltage

1. 220 V
2. 240 V
3. 280 V
4. 300 V

In the MKS system, the value of 3 kW is equal to

1. 013Hp
2. 3.013Hp
3. 4.021Hp
4. 5.021Hp

The resistivity of a conductor depends on

1. Length
2. Current
3. Voltage
4. Power

A 200 kVA transformer has a full load copper loss of 400 W and iron loss 200 W. The maximum efficiency of the transformer will occur when a total loss is

1. 500 W
2. 600 W
3. 1500 W
4. 1600 W

A 4 pole, three-phase induction motor is supplied by 50Hz frequency by a three-phase source. If the rotor of the motor rotates at 600 rpm, find the sli

1. 2
2. 0.4
3. 0.6
4. 0.8

TRIAC is operated at

1. Low Frequencies
2. Power Frequencies
3. High frequencies
4. All of these

Five thyristors each of 2000 V rating are connected in series with a power circuit of 5 V.K. Find the percentage series derating factor?

1. 40
2. 50
3. 60
4. 70

In an intrinsic semiconductor, the number of holes is ……. the number of electrons.

1. Equal to
2. More than
3. Less than
4. None of these

Find the value of emitter current of a transistor that has ADC = 0.5 and base current = 120 µA

1. 01 mA
2. 1.24 mA
3. 0.04 mA
4. 0.24mA

Electrical Engineering MCQs for NTS

Electrical Engineering MCQs (Part-03)

Which of the given material is used for making light-emitting diodes?

1. Si
2. Ge
3. GaAs
4. Fe

Noise is a function of which of the given term

1. Momentum
2. Acceleration
3. Voltage
4. Bandwidth

The displacement measuring Instrument LVDT works on the principle of

1. Fleming Left-hand rule
2. Mutual Induction
3. Linear induction
4. Linear capacitance

Which of the given material does not change the resistance with varying temperature

1. Gallium
2. Manganin
3. Tungsten
4. Copper

In a power plant, the maximum demand is 100MW, and the sum of individual maximum demand is 70 M.W. Calculate the diversity factor

1. 5
2. 0.6
3. 0.7
4. 0.8

Which of the following is a series type unbalanced fault that occurs in a power system

1. Single line to double line fault
2. Double line to double line fault
3. The line to line fault
4. Open conductor fault

The three-phase oil circuit breaker rated as 2000 MVA, 66 K.V., 6 SEC. Find the making current

1. 44 kA
2. 19.43 kA
3. 22.76 kA
4. 27.55 kA

In a three-phase induction motor, the rotor power output is 20 kW, and the value of the corresponding slip is 8 %. Find the rotor copper loss of the motor

1. 1288 W
2. 1596 W
3. 2033 W
4. 2522 W

Which of the given relays can resist the possible major fault in the transformer

1. Current relay
2. Frequency relay
3. Buchholz relay
4. Overcurrent relay

In a three-phase transformer, the primary winding is delta connected, and the secondary winding is star connected, and the secondary to primary turn ratio per phase is 15. If 240 V is applied to the transformer’s primary side, find the secondary voltage of the transformer.

1. 5532 V
2. 6625 V
3. 6235 V
4. 7325 V

Which of the given diode is called hot-carrier dioxide?

1. N. junction diode
2. Schottky diode
3. Light-emitting diode
4. Zener diode

In a transformer, the humming sound is primarily due to

1. Overflow of oil
2. Magnetostriction
3. Flux leakage
4. Lamination of transformer

When a 20 A current flows for 6 minutes, calculate the amount of electricity transferred.

1. 7200 C
2. 6400 C
3. 8400 C
4. 5400 C

Find the barrier potential for Si junction diode at 100 C, calculate its value at 400 C is 0.9 V

1. 75 V
2. 0.96 V
3. 1.20 V
4. 0.60

Electrical Engineering MCQs for Job Test

Electrical Engineering MCQs (Part-04)

An induction machine is operated with frequencies that are given in the ratio 3:7 without changing the voltage. Find the starting torque of the machine for the given frequencies

1. 2:7
2. 3:7
3. 4:7
4. 5:7

The voltage range is non uniform. Its type is

1. Electrostatic instrument
2. Potentiometer
3. Galvanometer
4. Multimeter

Which of the given test is used for the calculation of the inertia of the rotor?

1. Sinners test(Back to Backtest)
2. Low voltage test
3. High Voltage test
4. Retardation test

A galvanometer having the value of coil resistance is 120 Ω gives a full-scale deflection when a current of 3mA is passed through it. Find the value of the resistance, which can convert a galvanometer into an ammeter, giving a full-scale deflection for a current of 12 A.

1. 07 Ω
2. 0.09 Ω
3. 0.11 Ω
4. 0.03 Ω

Find the numbers of address lines needed to address a memory size 64K

1. 10
2. 12
3. 14
4. 16

A 3 phase Induction motor having 70 Hz frequency draws a power of 80 kW from mains. If the stator losses are 4kW and rotor emf oscillates at 120 oscillations per minute, find the rotor copper losses

1. 26 kW
2. 0.54 kW
3. 0.10 kW
4. 0.99 kW

In an induction motor, crawling is caused by

1. High Voltage
3. Harmonic produced in the motor
4. Improper design of machine

In a ferromagnetic material, the neighboring atomic magnetic moments are

1. Predominantly unequal in small regions of material.
2. Predominantly constant in small regions of material.
3. Predominantly unequal and parallel throughout the material.
4. Predominantly equal and parallel throughout the material.

N-type and P-type extrinsic semiconductors are formed by adding the impurities of which valency.

1. Tertavalent and pentavalent
2. Trivalent and pentavalent
3. Pentavalent and trivalent
4. Trivalent and tetravalent.

An 8 pole, 1600 rpm D.C. lap wound generator has 1680 conductors. If the flux per pole is 0.04 weber, find the emf of the generator.

1. 1600 V
2. 1792 V
3. 1982 V
4. 2020 V

The input voltage of a boost regulator is 8V, and the average output voltage is 24V. Find the duty cycle.

1. 1/3
2. 2/3
3. 5/3
4. 1

In which of the given single-phase motor, the rotor has no teeth or winding?

2. Capacitor start motor
3. A permanent capacitor run the motor
4. Hysteresis motor

1 volt can be expressed as

1. 1 joule/weber
2. 1 joule/ columb
3. 1 joule/ohm
4. 1 watt/ Joule

A single-phase having a rating of 11 kVA, 4400/440 V, 50 Hz, distribution transformer is to be connected as an auto-transformer to get an output voltage of 3260 V. Find its maximum kVA rating as an autotransformer.

1. 111
2. 121
3. 144
4. 169

The starting current of a three phase induction motor is 3 times the rated current, while the rated slip is 8 %. Find the ratio of starting toque to full load toque

1. 5
2. 0.75
3. 0.72
4. 0.80

The Ybus matrix of a 200 bus interlinked system is 70 % sparse. Find the number of transmission lines in the system

1. 8100
2. 7200
3. 5900
4. 4700

A negative sequence really is usually used to protect

1. A transformer
2. An Alternator
3. A transistor
4. A Junction

A potentiometer is usually a

1. Digital Instrument
2. Deflection type instrument
3. Null type instrument
4. None of these

An amplifier has a gain of 30 without feedback. If 20 % of the output voltage is a feedback using its resistance negative feedback circuit, find the overall gain?

1. 67
2. 4.28
3. 9.85
4. 7.47