Question

In an AC series circuit, the instantaneous current is zero when the instantaneous voltage is maximum, the circuit may be

• A. purely inductive
• B. pure capacitive
• C. pure resistive
• D. combination of an inductor and a capacitor

Answer 1

The correct option is A purely inductive

A

The device is inductor. In an inductor, the current lags the voltage by a phase difference of 90 degree. Hence when a sinusoidal voltage is applied to the inductor, the voltage lead, the current by one – fourth of a cycle or by a 90 degree phase angle. Current lags behind voltage, since inductor oppose the change in current. Changing current induces an emf. This is considered as an effective resistive of ithe inductor of AC.