Answer: 0.10 C.
- A 0.10 C
- B 0.20 C
- C 0.05 C
- D 0.40 C
Correct answer: A. 0.10 C
Explanation: The total charge is q = NΔΦ/R = 50 × 0.004/2 = 0.10 C.
As a magnet approaches a coil, flux rises steadily and a constant non-zero EMF is induced (Faraday's law). Once the magnet stops moving, flux stays constant and the induced EMF drops to zero - EMF only exists while flux is actively changing.
Concept context
Faraday's and Lenz's laws, motional EMF, self/mutual inductance, eddy currents, and the AC generator - how a changing magnetic flux creates an electric current.