NEET
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- NEET
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- Physics
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- Electromagnetic Induction
NEET · Physics · Electromagnetic Induction
A single circular metallic loop is held stationary. A bar magnet is...
A single circular metallic loop is held stationary. A bar magnet is moving along the axis of the loop. An observer, looking at the loop from the side of the magnet, observes that the induced current in the loop is counter-clockwise. Which of the following describes the possible pole of the magnet facing the loop and its state of motion?
Options
- AOnly the North pole facing the loop and moving towards it.
- BOnly the South pole facing the loop and moving away from it.
- CEither the North pole facing the loop and moving away from it, or the South pole facing the loop and moving towards it.
- DEither the North pole facing the loop and moving towards it, or the South pole facing the loop and moving away from it.
Correct answer
D. Either the North pole facing the loop and moving towards it, or the South pole facing the loop and moving away from it.
Step-by-step solution
An observer looking at the loop from the side of the magnet sees a counter-clockwise induced current.
According to the right-hand grip rule, a counter-clockwise current means the face of the loop towards the observer (and the magnet) acts as a North magnetic pole.
By Lenz's law, the induced magnetic pole opposes the change in magnetic flux that produces it. A North pole is induced on the loop's face either to repel an approaching North pole or to attract a receding South pole.
Therefore, the magnet must either have its North pole facing the loop and moving towards it, or its South pole facing the loop and moving away from it.
Answer: Either the North pole facing the loop and moving towards it, or the South pole facing the loop and moving away from it.
According to the right-hand grip rule, a counter-clockwise current means the face of the loop towards the observer (and the magnet) acts as a North magnetic pole.
By Lenz's law, the induced magnetic pole opposes the change in magnetic flux that produces it. A North pole is induced on the loop's face either to repel an approaching North pole or to attract a receding South pole.
Therefore, the magnet must either have its North pole facing the loop and moving towards it, or its South pole facing the loop and moving away from it.
Answer: Either the North pole facing the loop and moving towards it, or the South pole facing the loop and moving away from it.