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Question
Briefly explain various ways to increase the strength of the magnetic field produced by a given solenoid.
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Solution
The magnetic field inside a current-carrying solenoid is given by
B = μ0nI
where n is the number of turns per unit length in the solenoid, and I is the current through the wire.
As a result, increasing the current or the number of loops per metre would result in an increase in the magnetic field in the solenoid. Because the iron core is a magnet and is magnetised, it contributes flux to the solenoid's flux, hence increasing the magnetic field intensity.
The magnetic field strength produced by the solenoid can be raised by
- By inserting soft iron into the solenoid,
- By increasing the number of coil turns,
- By increasing the flow of electricity through the solenoid.
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