The equation of 50 Hz current sine wave having r.m.s. value of 60 A is____________?

A. 60 sin 25 t
B. 60 sin 50 t
C. 84.84 sin 3141
D. 42.42 sin 314 t

The power factor of a D.C. circuit is always__________?

A. Less than unity
B. Unity
C. Greater than unity
D. Zero

In a pure inductive circuit if the supply frequency is reduced to 1/2, the current will__________?

A. Be reduced by half
B. Be doubled
C. Be four times as high
D. Be reduced to one fourth

In a pure capacitive circuit if the supply frequency is reduced to 1/2, the current will__________?

A. Be reduced by half
B. Be doubled
C. Be four times at high
D. Be reduced to one fourth

An A.C. voltage is impressed across a pure resistance of 3.5 ohms in parallel with a pure inductance of impedance of 3.5 ohms?

A. The current through the resistance is more
B. The current through the resistance is less
C. Both resistance and inductance carry equal currents
D. None of the above

The product of apparent power and cosine of the phase angle between circuit voltage and current is

A. True power
B. Reactive power
C. Volt-amperes
D. Instantaneous power

A pure capacitor connected across an A.C. voltage consumed 50 W. This is due to________?

A. The capacitive reactance in ohms
B. The current flowing in capacitor
C. The size of the capacitor being quite big
D. The statement is incorrect

When an alternating current passes through an ohmic resistance the electrical power converted into heat is__________?

A. Apparent power
B. True power
C. Reactive power
D. None of the above

In each of the three coils of a three phase generator, an alternating voltage having an r.m.s. value of 220 V is induced. Which of the following values is indicated by the voltmeters ______?

A. 220 v
B. 220v3v
C. 220/v3 v
D. None of the above

The power factor at resonance in R-L- C parallel circuit is________?

A. Zero
B. 0.08 lagging
C. 0.8 leading
D. Unity