MCQ
When a coil is moved or rotated relative a fixed magnet then.
- Avoltage increased
- Bcurrent is induced
- Cboth
- Dvoltage is induced
✓
Answer
- current is induced
Explanation:
After performing a large number of experiments, Faraday and Henry made the following observations about electromagnetic induction
- a current is induced in a coil when it is moved(rotated)relative to a fixed magnet.
- a current is also induced in a fixed coil when a magnet is moved (or rotated)relative to the fixed coil.
- no current is induced in a coil when the coil and magnet both are stationary relative to one another.
- when the direction of motion of coil (or magnet) is reversed , the direction of current induced in the coil also get reversed.
- the magnitude of current induced in the coil can be increased.
- by winding the coil on a soft iron core.
- by increasing the number of turns in the coil.
- by increasing the strength of magnet.
- by increasing the speed of rotation of coil (magnet).
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