Circuits and Circuit Theory

31.In a pure capacitive circuit if the supply frequency is reduced to 1/2, the current will

1. be reduced by half
2. be doubled
3. be four times at high
4. be reduced to one fourth

View answer

32.In a pure inductive circuit

1. the current is in phase with the voltage
2. the current lags behind the voltage by 90°
3. the current leads the voltage by 90°
4. the current can lead or lag by 90°

View answer

33.In a pure inductive circuit if the supply frequency is reduced to 1/2, the current will

1. be reduced by half
2. be doubled
3. be four times as high
4. be reduced to one fourth

View answer

34.In a pure resistive circuit

1. current lags behind the voltage by 90°
2. current leads the voltage by 90°
3. current can lead or lag the voltage by 90°
4. current is in phase with the voltage

View answer

35.In a purely inductive circuit

1. actual power is zero
2. reactive power is zero
3. apparent power is zero
4. none of above is zero

View answer

36.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. exchange of power does not take place between resistance and the supply line
5. all above are correct

View answer

37.In a series L-C circuit at the resonant frequency the

1. current is maximum
2. current is minimum
3. impedance is maximum
4. voltage across C is minimum

View answer

38.In a series resonant circuit, the impedance of the circuit is

1. minimum
2. maximum
3. zero
4. none of the above

View answer

39.In a sine wave the slope is constant

1. between 0° and 90°
2. between 90° and 180°
3. between 180° and 270°
4. no where

View answer

40.In a three-phase supply floating neutral is undesirable because it way give rise to

1. high voltage across the load
2. low voltage across the load
3. unequal line voltages across the load
4. none

View answer