A conducting circular loop is placed in a uniform magnetic field B = 0.020 T with its plane perpendicular to the field. The radius of the loop starts shrinking at a constant rate of 1.0 mm/s. Find the induced e.m.f in the loop at an instant when the radius is 2cm?

Question

(a) $25 \mu V$
(b) $2.5 \mu V$
(c) $0.25 \mu V$
(d) $0.025 \mu V$