An elastic conducting material is stretched into a circular loop of 9.65 cm radius. It is placed with its plane perpendicular to a uniform 1.14 T magnetic field. When released, the radius of the loop starts to shrink at an instantaneous rate of 75.6 cm/s. What emf is induced in volts in the loop at that instant?

The induced emf in the coil is 0.522 volts.                        

Explanation:

Given that,

Radius of the circular loop, r = 9.65 cm

It is placed with its plane perpendicular to a uniform 1.14 T magnetic field.

The radius of the loop starts to shrink at an instantaneous rate of 75.6 cm/s ,

Due to the shrinking of radius of the loop, an emf induced in it. It is given by :

So, the induced emf in the coil is 0.522 volts.                                

r=rho l/a where a is the area, l is the length and rho is resistivity so the greater the area the lesser the resistance thats why the earth pin is thicker bcos current follow the shortest path, so less resistive .