Explanation:
Given that,
Radius of the circular loop, r = 3.5 cm = 0.035 m
(a) During a 0.12-s time interval, the magnitude of the field increases uniformly from 0.2 T to 0.5 T. Due to the change in the magnetic field, an emf will induced in it. The magnitude of induced emf is given by :
So, the magnitude of the emf induced in the loop during the time interval is .
(b) The negative sign shows that the direction of induced emf in the loop is in anitclockwise direction.