E E

The period of wave

• The same as frequency

• Time required to complete one cycle

• Expressed in amprres

• None of the above

What is the RMS value of an AC current

• The steady current will charge a battery at the same rate as the actual current

• Its average value

• Its peak value

• The steady current that produce the same rate of heating a resistor as the actual current

The voltage of domestic supply is 220 v. This figure represents?

• Mean value

• Rms value

• Peak value

• Average value

In the case of an unsymetrical alternating current the average value must always be taken over

• Unsymetrical part of the wave form

• The quarter cycle

• The half cycle

• The whole cycle

The RMS value and mean value is the same in the case of

• Triangular wave

• Sine wave

• Square wave

• Half wave rectified sine wave

For the same peak value which of the following wave will have the highest rms value

• Square wave

• Half wave rectifier sine wave

• Triangular wave

• Sine wave

What will be the phase angle between two alternating waves of equal frequency, when one wave attains maximum value the other is at zero value?

• 0°

• 45°

• 90°

• 180°

In pure resistive circuit

• Current lags behind the voltage by 90°

• Curents lead the voltage by 90°

• Current can lead or lag the voltage by 90°

• Current is in phase with the voltage

Power factor resistive circuit

• Zero

• Lagging

• Leading

• Unity

In a purely inductive circuit, the current lags the voltage by

• One half of the cycle

• One cycle

• Three fourths of the cycle

• One fourth of the cycle