Delhi Police Constable Exam Model Paper 8

The correct answer is Periodically.
CONCEPT:

The electric current flows in two ways: Alternating current and Direct Current

• Direct current flows only in one direction.

● Alternating current: The electric current whose direction changes periodically is called electric current.

● Alternating current reverses its direction periodically.
●It also changes its magnitude periodically because of the induced electromagnetic force.
●For Alternating current both magnitude and direction change. The frequency of the alternating current in the Indian power supply is 50 Hz. The time period is 1/50 = 20 msec.
EXPLANATION:
● In Alternating Current (AC), the direction and magnitude of the current vary periodically. So option 2 is correct.