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Question
- What name is given to a cylindrical coil of diameter less than its length?
- If a piece of soft iron is placed inside the coil mentioned in part (a) and current is passed in the coil from a battery, what name is then given to the device so obtained?
- Give one use of the device mentioned in part (b).
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Solution
- Solenoid is a cylindrical coil of diameter less than its length.
- The device so obtained is electromagnet.
- It is used in electric bell.
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