Practice question · Multiple choice
A loop sits in a magnetic field that is steadily decreasing. Which way does the induced current flow?
Hints
- Lenz’s law says the current opposes the CHANGE, not the field.
- If the flux is falling, opposing that change means acting to keep it up.
Show the answer
C. In the direction that maintains the existing flux through the loop
Why
Lenz’s law opposes the change. With the flux falling, the induced current flows so as to maintain it, reinforcing the field rather than fighting it. Only an increasing flux produces an opposing current.
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