8) A flat circular loop having one turn and radius 5.0 cm is positioned with its plane perpendicular to a uniform 0.60-T magnetic field. The area of the loop is suddenly reduced to essentially zero in 0.50 ms. What emf is induced in the loop

EMF induced in the loop is 9.4 V

Explanation:

As we know that initial magnetic flux of the loop is given as

As soon as the area of the loop becomes zero the final magnetic flux of the loop is ZERO

Now as per faraday's law of electromagnetic induction the EMF is induced due to rate of change in magnetic flux

so we will have

so we will have

if the person is shown to have +90n, then ans is -10n.

if the person is shown to have -90n, then ans is +10n.