A uniform magnetic field B is directed out of the page, as shown above. A loop of wire of area 0.40 m2 is in the plane of the page. At a certain instant the field has a magnitude of 3.0 T and is decreasing at the rate of 0.50 T/*. The magnitude of the induced emf in the wire loop at this instant is most nearly
(A) 0.20 V
(B) 0.60 V
(C) 1.2 V
(D) 1.5 V
(E) 2.8 V
The correct option is: (A) 0.20 V
Explanation:
Use a 1 second time **, the field would decrease to 2.5 T in that time.
Then apply ε = ΔФ / t
ε = ( BAf – BAi ) / t … ε = A (Bf – **) … ε = (0.4)(3 – 2.5) / 1
