試題詳解

18. The figure shows two regions of uniform magnetic field. On the left of the dashed line, B₁ = 4.00r² in teslas and seconds, and on the right, B₂ = 60.0 T. The dimensions are L₁ = 2.00 m and L₂ = 3.00 m. The circuit includes an ideal 60 V battery, and the total resistance is 15.0 Ω. What is the current ( A ) in the circuit at time t = 3.00 s?

(A) 9.83,
(B) 1.91,
(C) 5.60,
(D) 16.8,
(E) 2.50.