(i) As the diaphragm vibrates, it causes the coil to move back and forth in the magnetic field cutting the field lines. This causes a varying electro-magnetic force to be induced in the coil which causes a varying current to flow.
(ii) - Increasing number of turns in the coil
- Increasing the strength of the magnet
johnmulu answered the question on June 5, 2017 at 11:39
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