A 39-turn circular coil of radius 3.20 cm and resistance 1.00 Ω is placed in a magnetic field directed perpendicular to the plane of the coil. The magnitude of the magnetic field varies in time according to the expression B = 0.010 0t + 0.040 0t2, where B is in teslas and t is in seconds. Calculate the induced emf in the coil at t = 5.40 s.

Answer 1

39- turn coil
3.20 cm
1.00 Ω
B= 0.0100t + 0.0400t2
T= 5.40s

lƩl =ΔφB/Δt = N (dB/dt)A


=N[d/dt (0.0100t + 0.0400 t^2)A
=39(0.0100 + 0.0800(5.40))[π(0.0320)^2]
=0.05545
=5.55 x 10^-2 V
=55.5 mV