試題詳解

53. A 30-turn circular coil of radius 1 m and resistance 1 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 = 0.1 t + 0.04 t² , where B is in tesla and t is in second. Calculate the induced emf in the coil at t = 5 s.
(A) 27 V
(B) 37 V
(C) 47 V
(D) 57 V
(E) 67 V