Alternating Current

What is meant by Alternating Current?

• An electric current whose direction change periodically

• An electric current whose magnitude change periodically

• An electric current whose magnitude and direction change periodically

• An electric current whose magnitude or direction change periodically

The graph of alternating current or alternating voltage is a_________form.

• square

• sinusoidal

• triangle

• sawtooth

• Instantaneous current

• Lowest current

• RMS current

• Peak current

Root mean square current  is defined as

• the value of the steady DC which produces the same power in a resistor as the mean (average) power produced by the AC.

• the value of the steady DC which produces the same power in a capacitor as the mean (average) power produced by the AC.

• the value of the steady AC which produces the same power in a resistor as the mean (average) power produced by the DC.

• the value of the steady AC which produces the same power in a capacitor as the mean (average) power produced by the DC.

• peak

• least

• average

• effective

What is phasor diagram?

• A vector that rotates clockwise about its axis with constant angular velocity

• A vector that rotates anticlockwise about its axis with constant angular velocity

• A vector that rotates anticlockwise about its axis with constant angular acceleration

• A vector that rotates clockwise about its axis with constant angular acceleration

Phase angle is the __________

• total phase between current and voltage in DC circuit.

• phase difference between current and voltage in DC circuit.

• total phase between current and voltage in AC circuit.

• phase difference between current and voltage in AC circuit.

In a pure resistor circuit, _______________

• the voltage and current are in antiphase.

• the voltage and current are in phase.

In a pure capacitor circuit, ______________

• the current and voltage are in phase

• the current and voltage are in antiphase

In a pure inductor circuit, ______________

• the current and voltage are in antiphase.

• the current and voltage are in phase.