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Two identical circular metal wire loops lie flat on a table and do not touch each other. The current in loop A is increasing with time. As a result, loop B will
- stay at rest
- move toward loop A
- move away from loop A
- spin about its centre of mass while the centre of mass remains fixed
Correct answer: move away from loop A
Solution
As the current in loop A increases, it creates a changing magnetic field that induces an electromotive force (EMF) in loop B according to Faraday's law of electromagnetic induction. This induced current in loop B will generate its own magnetic field that opposes the change in the magnetic field from loop A, resulting in a repulsive force that causes loop B to move away from loop A.
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