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Question
The diagram shows a current-carrying coil passing through a cardboard sheet. Draw three magnetic lines of force on the board.

State two factors on which magnitude of magnetic field at the centre depends.
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Solution
Figure shows the magnetic lines of force due to current-carrying coil.

The magnitude of the magnetic field at the center of coil depends on:
(i) the strength of the current in the coil, and
(ii) the radius of coil.
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