Question: The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA The power drawn by the circuit is__________?

• 1. 12 kW
• 2. 22 kW
• 3. 32 kW
• 4. 64 kW

Question: In an AC. circuit, a low value of kVAR compared with kW indicates_________?

• 1. low efficiency
• 2. high power factor
• 3. unity power factor
• 4. maximum load current

Question: Which of the following coil will have large resonant frequency __________?

• 1. A coil with large resistance
• 2. A coil with low resistance
• 3. A coil with large distributed capacitance
• 4. A coil with low distributed capacitance

Question: If a sinusoidal wave has frequency of 50 Hz with 30 A r.m.s. current which of the following equation represents this wave_________ ?

• 1. 42.42 sin 3141
• 2. 60 sin 25 t
• 3. 30 sin 50 t
• 4. 84.84 sin 25 t

Question: In a R-L-C circuit_________?

• 1. power is consumed in resistance and is equal to I R
• 2. exchange of power takes place between inductor and supply line
• 3. exchange of power takes place between capacitor and supply line
• 4. all above are correct

Question: If resistance is 20 Q. and inductance is 27 in a R-L series circuit, then time constant of this circuit will be________?

• 1. 0.001 s
• 2. 0.1 s
• 3. 10 s
• 4. 100 s

Question: The safest value of current the human body can carry for more than 3 second is_________?

• 1. 4 mA
• 2. 9 mA
• 3. 15 mA
• 4. 25 mA

Question: Time constant of a circuit is the time in seconds taken after the application of voltage to each___________?

• 1. 25% of maximum value
• 2. 50% of maximum value
• 3. 63% of maximum value
• 4. 90% of the maximum value

Question: Power factor of electric bulb is__________?

• 1. zero
• 2. lagging
• 3. leading
• 4. unity

Question: Which of the following circuit component opposes the change in the circuit voltage ?

• 1. Inductance
• 2. Capacitance
• 3. Conductance
• 4. Resistance