Answer:
The induced emf in the loop is 0.452 volts.
Explanation:
Given that,
Radius of the circular loop, r = 12 cm = 0.012 m
Magnetic field, B = 0.8 T
When released, the radius of the loop starts to shrink at an instantaneous rate of, [tex]\dfrac{dr}{dt}=75\ cm/s=0.75\ m/s[/tex]
The induced emf in the loop is equal to the rate of change of magnetic flux. It is given by :
[tex]\epsilon=\dfrac{-d\phi}{dt}\\\\\epsilon=\dfrac{-d(BA)}{dt}\\\\\epsilon=B\dfrac{-d(\pi r^2)}{dt}\\\\\epsilon=2\pi rB\dfrac{-dr}{dt}\\\\\epsilon=2\pi \times 0.12\times 0.8\times 0.75\\\\\epsilon=0.452\ V[/tex]
So, the induced emf in the loop is 0.452 volts.
