Practice portal › Electromagnetic Induction › Applications and Conceptual
Asked in GSEB Board July 2023 · Applications and conceptual
Idea: ask what would happen if the induced current did not oppose the change.
Suppose a magnet pushed towards a coil induced a current that attracted it. The magnet would speed up by itself, the flux would change faster, the current would grow: energy from nothing.
That violates conservation of energy, so the induced current must oppose the change.
Because of this opposition, work has to be done to move the magnet, and that work appears as the electrical energy (heat) of the induced current.
So Lenz's law is a consequence of the law of conservation of energy.
Reading this solution needs no sign-in. You only sign in to practise against the clock and keep your progress.
Practise this with a timer