MCQ
A magnet is made to oscillate with a particular frequency, passing through a coil as shown in figure. The time variation of the magnitude of $e.m.f$. generated across the coil during one cycle is
- ✓
- B
- C
- D
✓
Answer
Correct option: A.
a
(a) when north pole of magnet approaches the one face of coil, then the force of the coil becomes a north pole to oppose this motion and current flows anticlockwise thus, in this case emf is developed in the coil and when it completes on half motion it is momentarily at rest and no emf is present. now south pole approaches the current mow flows in clockwise direction and again an emf is developed in the coil. this variation is shown in figure.
(a) when north pole of magnet approaches the one face of coil, then the force of the coil becomes a north pole to oppose this motion and current flows anticlockwise thus, in this case emf is developed in the coil and when it completes on half motion it is momentarily at rest and no emf is present. now south pole approaches the current mow flows in clockwise direction and again an emf is developed in the coil. this variation is shown in figure.
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