Power factor of electric bulb is__________?

A. Zero
B. Lagging
C. Leading
D. Unity

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

A. 25% of maximum value
B. 50% of maximum value
C. 63% of maximum value
D. 90% of the maximum value

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

A. 4 ma
B. 9 ma
C. 15 ma
D. 25 ma

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

A. 0.001 s
B. 0.1 s
C. 10 s
D. 100 s

In a R-L-C circuit_________?

A. power is consumed in resistance and is equal to i r
B. exchange of power takes place between inductor and supply line
C. exchange of power takes place between capacitor and supply line
D. exchange of power does not take place between resistance and the supply line

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

A. 42.42 sin 3141
B. 60 sin 25 t
C. 30 sin 50 t
D. 84.84 sin 25 t

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

A. A coil with large resistance
B. A coil with low resistance
C. A coil with large distributed capacitance
D. A coil with low distributed capacitance

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

A. Low efficiency
B. High power factor
C. Unity power factor
D. Maximum load current

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

A. 12 kw
B. 22 kw
C. 32 kw
D. 64 kw

A pure inductance connected across 250 V, 50 Hz supply consumes 100 W. This consumption can be attributed to_________?

A. The big size of the inductor
B. The reactance of the inductor
C. The current flowing in the inductor
D. The statement given is false