Answer: oppose the change in flux that produces it.
- A oppose the change in flux that produces it
- B aid the change in flux
- C have no effect on the flux
- D double the flux
Correct answer: A. oppose the change in flux that produces it
Explanation: Lenz law states the induced current opposes the change in magnetic flux, consistent with energy conservation.
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.