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A metallic ring is kept in a horizontal position, and a bar magnet is released so that it falls through the ring with its length aligned along the ring’s axis. The magnet’s acceleration while falling is
- equal to g
- less than g
- greater than g
- dependent on the ring’s diameter and the magnet’s length
Correct answer: less than g
Solution
The falling magnet induces currents in the ring that oppose its motion, producing a retarding force, so its acceleration is less than g.
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