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The advantage of the double squirrel cage induction motor over a single cage rotor is that its _______

1. Efficiency is higher
2. Power factor is higher
3. Slip is larger
4. Starting current is lower

✅ Correct Answer: 4

A 16-pole 3-phase 60 Hz induction motor is operating at a speed of 150 rpm. The frequency of the rotor current of the motor in Hz is __________

1. 20
2. 40
3. 30
4. 10

✅ Correct Answer: 2

Calculate the amplitude of the sinusoidal waveform

1. 710
2. 715
3. 716
4. 718

✅ Correct Answer: 2

R.M.S value of the sinusoidal waveform V=48sin(6.5?t+89?ï¿½46.8).

1. 33.94 V
2. 33.56 V
3. 33.12 V
4. 33.78 V

✅ Correct Answer: 1

The short circuit test on a 3-? induction motor is conducted at a rotor speed of _______

1. Zero
2. < Ns
3. > Ns
4. Ns

✅ Correct Answer: 1

If induction motor air gap power is 10 KW and mechanically developed power is 8 KW then rotor ohmic loss will be _________ KW.

1. 1
2. 2
3. 3
4. 4

✅ Correct Answer: 2

A 3-phase induction machine draws active power P and reactive power Q from the grid. If it is operated as a generator then P and Q will be _________

1. Positive and Negative
2. Negative and Positive
3. Positive and Positive
4. Negative and Negative

✅ Correct Answer: 2

The slope of the V-I curve is 39.1ï¿½. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.

1. .81 ?
2. .36 ?
3. .75 ?
4. .84 ?

✅ Correct Answer: 1

If induction motor air gap power is 48 KW and gross developed power is 28 KW then rotor ohmic loss will be _________ KW.

1. 10
2. 20
3. 30
4. 40

✅ Correct Answer: 2

The power factor of a squirrel cage induction motor is ___________

1. Low at light load only
2. Low at heavy loads only
3. Low at the light and heavy loads both
4. Low at rate load only

✅ Correct Answer: 1

Calculate the active power in a .154 H inductor.

1. 22 W
2. 14 W
3. 45 W
4. 0 W

✅ Correct Answer: 4

Calculate the time period of the waveform z(t)=24sin(?t+?ï¿½4)+4sin(2?t+?ï¿½6).

1. 2 sec
2. 3 sec
3. 4 sec
4. 1 sec

✅ Correct Answer: 1

Calculate the total heat dissipated in a resistor of 50 ? when 1.4 A current flows through it.

1. 98 W
2. 92 W
3. 91 W
4. 93 W

✅ Correct Answer: 1

Calculate mark to space ratio if the system is on for 26.3 sec and off for 24.2 sec.

1. 1.086
2. 1.042
3. 1.214
4. 1.876

✅ Correct Answer: 1

In the chopper circuit commutation times are _______

1. Current commutation is equal to voltage commutation
2. Current commutation is less as compared to that of voltage commutation
3. Current commutation is more as compared to that of voltage commutation
4. Both commutation techniques are not comparable

✅ Correct Answer: 2

The generated e.m.f from 4-pole armature having 1 conductors driven at 1 rev/sec having flux per pole as 10 Wb with wave winding is ___________

1. 30 V
2. 40 V
3. 70 V
4. 20 V

✅ Correct Answer: 4

Calculate the moment of inertia of the sphere having a mass of 8.4 kg and radius of 61 cm.

1. 3.124 kgm2
2. 3.125 kgm2
3. 4.545 kgm2
4. 5.552 kgm2

✅ Correct Answer: 2

The most suitable control-motor application is __________

1. AC shunt motor
2. DC separately motor
3. AC one-phase induction motor
4. DC shunt motor

✅ Correct Answer: 2

In a DC series motor the e.m.f developed is proportional to _______

1. Nï¿½Ia
2. Nï¿½Ia2
3. Nï¿½Ia3
4. Nï¿½Ia.5

✅ Correct Answer: 1

Calculate the value of the time period if the frequency of the signal is .07 sec.

1. 14.28 sec
2. 14.31 sec
3. 14.23 sec
4. 14.78 sec

✅ Correct Answer: 1

The slope of the V-I curve is 13.89ï¿½. Calculate the value of resistance.

1. .247 ?
2. .345 ?
3. .231 ?
4. .222 ?

✅ Correct Answer: 1

In a DC shunt motor the e.m.f developed is proportional to ___________

1. Ia
2. Ia2
3. Ia3
4. Iao

✅ Correct Answer: 4

Calculate the power factor angle during the resonance condition.

1. 0ï¿½
2. 10ï¿½
3. 80ï¿½
4. 90ï¿½

✅ Correct Answer: 4

Calculate the value of the duty cycle if the system is on for 5 sec and off for inf sec.12.

1. 0
2. 0.4
3. 0.2
4. 0.1

✅ Correct Answer: 1

Calculate the value of the frequency of the AC supply in India.

1. 0 Hz
2. 50 Hz
3. 49 Hz
4. 60 Hz

✅ Correct Answer: 2

What is the formula for the maximum active power in the cylindrical rotor synchronous machine? (Eb represents armature emf Vt represents terminal voltage ? represents rotor angle X represents reactance)

1. Ebï¿½Vtï¿½sin?ï¿½X
2. Ebï¿½Vt2ï¿½X
3. Eb2ï¿½Vtï¿½sin?ï¿½X
4. Ebï¿½Vtï¿½X

✅ Correct Answer: 4

Calculate the power factor if the power angle is 36.86ï¿½.

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

✅ Correct Answer: 1

Calculate the reactive power in a 2.2 ? resistor.

1. 1.5 VAR
2. 2.6 VAR
3. 0 VAR
4. 1.9 VAR

✅ Correct Answer: 3

What is the unit of the distance?

1. m
2. m/s
3. atm/m
4. Volt

✅ Correct Answer: 1

Calculate the reactive power in a 7.2545 ? resistor.

1. 1.221 VAR
2. 2.611 VAR
3. 0 VAR
4. 1.997 VAR

✅ Correct Answer: 3

The slope of the V-I curve is 180o. Calculate the value of resistance. The graph is parallel to the x-axis.9.

1. 1.47 ?
2. 1.81 ?
3. 0 ?
4. 4.12 ?

✅ Correct Answer: 3

Calculate the value of the duty cycle if the system is on for 1 sec and off for 0 sec.1

1. 1
2. 0.4
3. 0.1
4. 0.6

✅ Correct Answer: 1

The phase difference between voltage and current in the choke coil.

1. 90ï¿½
2. 40ï¿½
3. 50ï¿½
4. 68ï¿½

✅ Correct Answer: 1

A 32-pole 3-phase 70 Hz induction motor is operating at a speed of 112 rpm. The frequency of the rotor current the motor in Hz is __________

1. 40.2
2. 46.1
3. 40.1
4. 40.6

✅ Correct Answer: 3

A 20-pole 3-phase 90 Hz induction motor is operating at a speed of _______ rpm. The frequency of the rotor current of the motor in Hz is 20.

1. 418.56
2. 420.12
3. 421.23
4. 422.45

✅ Correct Answer: 2

Calculate the amplitude of the sinusoidal waveform z(t)=.27sin(.369?t+.142?ï¿½4.25).

1. 0.287
2. 0.27
3. 0.287
4. 0.216

✅ Correct Answer: 2

R.M.S value of the sinusoidal waveform q(t)=2.11cos(87.25t+78?ï¿½478.23).

1. 1.49 V
2. 1.56 V
3. 1.12 V
4. 1.78 V

✅ Correct Answer: 1

The no-load circuit test on a 3-? induction motor is conducted at a rotor speed of _______

1. Zero
2. < Ns
3. > Ns
4. Ns

✅ Correct Answer: 4

If induction motor air gap power is 67 KW and mechanically developed power is 26 KW then rotor ohmic loss will be _________ KW.

1. 41
2. 42
3. 43
4. 44

✅ Correct Answer: 1

Calculate the line voltage in star connection when phase voltage=45 V.

1. 77.9 V
2. 77.6 V
3. 77.2 V
4. 77.8 V

✅ Correct Answer: 1

The slope of the V-I curve is 1.1ï¿½. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.

1. .019 ?
2. .036 ?
3. .075 ?
4. .084 ?

✅ Correct Answer: 1

If induction motor rotor power is 157.5 KW and gross developed power is 79.9 KW then rotor ohmic loss will be _________ KW.

1. 77.5
2. 77.6
3. 76.9
4. 77.1

✅ Correct Answer: 2

The power factor of a squirrel cage induction motor generally is ___________

1. .6-.8
2. .1-.2
3. .2-.4
4. .5-.7

✅ Correct Answer: 1

Calculate the active power in a .89 H inductor.

1. 1.535 W
2. 0 W
3. 2.484 W
4. 1.598 W

✅ Correct Answer: 2

Calculate the time period of the waveform i(t)=sin(?t+6?ï¿½4)+sin(?t+5?ï¿½6).

1. 2 sec
2. 4 sec
3. 5 sec
4. 3 sec

✅ Correct Answer: 1

Calculate the total heat dissipated in a rotor resistor of 14.23 ? when .65 A current flows through it.

1. 6.45 W
2. 6.01 W
3. 6.78 W
4. 6.98 W

✅ Correct Answer: 2

Calculate mark to space ratio if the system is on for 4.3 sec and off for 78.2 sec.

1. 0.054
2. 0.047
3. 0.039
4. 0.018

✅ Correct Answer: 1

In the rotor voltage injection method when an external voltage source is in phase with the main voltage then speed will ___________

1. Increase
2. Decrease
3. Remain unchanged
4. First increases then decrease

✅ Correct Answer: 1

A 2-pole 3-phase ______ Hz induction motor is operating at a speed of 550 rpm. The frequency of the rotor current of the motor in Hz is 2.

1. 9.98
2. 9.71
3. 9.12
4. 9.37

✅ Correct Answer: 4

Calculate the average value of the sinusoidal waveform x(t)=848sin(1.65?t+2?ï¿½0.68).

1. 0
2. 78 V
3. 15 V
4. 85 V

✅ Correct Answer: 1

R.M.S value of the periodic square waveform of amplitude 72 V.

1. 72 V
2. 56 V
3. 12 V
4. 33 V

✅ Correct Answer: 1

In the rotor voltage injection method when an external voltage source is in opposite phase with the main voltage then speed will ___________

1. Increase
2. Decrease
3. Remain unchanged
4. First increases then decrease

✅ Correct Answer: 2

The slope of the V-I curve is 9.1ï¿½. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.

1. 16 ?
2. 26 ?
3. 25 ?
4. 44 ?

✅ Correct Answer: 1

If induction motor air gap power is 1.8 KW and gross developed power is .1 KW then rotor ohmic loss will be _________ KW.

1. 1.7
2. 2.7
3. 3.7
4. 4.7

✅ Correct Answer: 1

The power factor of a squirrel cage induction motor is ___________

1. High at light load only
2. High at heavy loads only
3. Low at the light and heavy loads both
4. Low at rate load only

✅ Correct Answer: 2

At low values of slip the electromagnetic torque is directly proportional to ___________

1. s
2. s2
3. s3
4. s4

✅ Correct Answer: 1

Calculate the time period of the waveform v(t)=12sin(8?t+8?ï¿½15)+144sin(2?t+?ï¿½6)+ 445sin(?t+7?ï¿½6).

1. 8 sec
2. 4 sec
3. 7 sec
4. 3 sec

✅ Correct Answer: 2

Calculate the total heat dissipated in a resistor of 44 ? when 0 A current flows through it.

1. 0 W
2. 2 W
3. 1.5 W
4. .3 W

✅ Correct Answer: 1

The value of slip at which maximum torque occurs ________

1. R2ï¿½X2
2. 4R2ï¿½X2
3. 2R2ï¿½X2
4. R2ï¿½3X2

✅ Correct Answer: 1

Calculate the voltage regulation in the synchronous machine if the no-load voltage is 12 V and the full load voltage is 15V.

1. -20%
2. -40%
3. -60%
4. -80%

✅ Correct Answer: 1

Calculate the condition for maximum voltage regulation in the synchronous machine.

1. ?=?s
2. ?=2?s
3. ?=4?s
4. ?=8?s

✅ Correct Answer: 1

R.M.S value of the sinusoidal waveform v(t)=211sin(7.25t+7?ï¿½78.3).

1. 149.19 V
2. 156.23 V
3. 116.57 V
4. 178.64 V

✅ Correct Answer: 1

Calculate the peak value of sinusoidal waveform if the r.m.s value is 21 V.29.69 V

1. 29.69 V
2. 48.74 V
3. 69.23 V
4. 25.74 V

✅ Correct Answer: 1

If induction motor air gap power is 2 KW and mechanically developed power is 1 KW then rotor ohmic loss will be _________ KW.7.

1. 1
2. 2
3. 3
4. 4

✅ Correct Answer: 1

Calculate the line voltage in the delta connection when phase voltage=45 V.

1. 46 V
2. 47 V
3. 45 V
4. 78 V

✅ Correct Answer: 3

The slope of the V-I curve is 35.48ï¿½. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.

1. 0.452 ?
2. 0.462 ?
3. 0.752 ?
4. 0.712 ?

✅ Correct Answer: 4

Calculate the line current in the delta connection when phase current=17 A.

1. 29.44 A
2. 24.64 A
3. 23.48 A
4. 26.56 A

✅ Correct Answer: 1

Calculate the active power in a 168.12 H inductor.

1. 65 W
2. 0 W
3. 68 W
4. 64 W

✅ Correct Answer: 2

Calculate the maximum value of slip when rotor resistance is 2 ? and rotor reactance is 3 ?.

1. 0.66
2. 0.33
3. 0.44
4. 0.99

✅ Correct Answer: 1

Calculate the total heat dissipated in a rotor resistor of 21 ? when .81 A current flows through it.

1. 13.77 W
2. 12.56 W
3. 46.45 W
4. 13.98 W

✅ Correct Answer: 1

Calculate the active power in an 8.12 F capacitor.

1. 89 W
2. 41 W
3. 0 W
4. 48 W

✅ Correct Answer: 3

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