1. What will be the value of current (in A) in a 50 cm long air-core solenoid, if the value of magnetic field at the center of the solenoid is 5 mT and the solenoid has 300 turns ?

6.63

5.63

4.36

8.25

Answer: 6.63

Explanation:


2. Determine the maximum flux density (in T} of a material having eddy current coefficient of 2, thickness of 4 mm, volume of 20 cu. meter, which is supplied by a frequency of 50 Hz when the material has eddy current loss of 6 W ?

2.24

3.34

1.94

1.21

Answer: 1.94

Explanation:


3. What is the peak-to-peak value of a sinusoidal voltage (in V) having average value of 100 V ?

141.44

159.98

282.88

313.97

Answer: 313.97

Explanation:


4. Calculate the phase angle between the voltage and current phasor of a series RL circuit having resistance of 65 Ohms and inductive reactance of 37.53 Ohms when supplied by a frequency of 60 Hz ?

15

30

45

60

Answer: 30

Explanation:


5. Calculate the value of resonant frequency (in kHz) of a tank circuit having capacitance of 0.01 mF and inductance of 0.01 mH ?

0.1591

1.591

15.91

159.1

Answer: 15.91

Explanation:


6. Calculate the induced emf (in V) in the inductor of a series RL circuit having inductance of 1.8 H and resistance of 90 Ohms after 20 milli-seconds, when supplied by a 20 V DC source ?

7.36

10.03

14.76

20

Answer: 7.36

Explanation:


7. A delta connected 3-phase circuit has three equal resistances of 36 Ohms in each phase. What is the value of per phase resistance (in Ohms) of the equivalent star connected circuit ?

12

36

84

108

Answer: 12

Explanation:


8. Calculate the power factor of an AC circuit having an impedance of 16 Ohms, if a 4 A current flows through it and its average power consumption is 200 W ?

0.68

0.78

0.88

0.98

Answer: 0.78

Explanation:


9. Power consumed by a balanced star connected 3-phase load is measured using two-wattmeter method. The phase voltage and phase current in the load is 220 V and 10 A respectively. What will be difference in reading (in W) of the Mo wattmeter, if the power factor of the system is 0.8 lagging ?

2861.2

2286.3

3810.5

3048.4

Answer: 2286.3

Explanation:


10. A house has 5 fans of 70 W each that operate for 16 hours a day and one washing machine of 2000 W that operates for 1 hour per day in the month of June. What is the energy consumption (in kWh) of the house in the month of June ?

228

235.6

350

486.6

Answer: 228

Explanation: