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Question
Describe a simple Experiment to demonstrate that there Exists a magnetic field around a current-carrying conductor.
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Solution
The conductor is kept in N-S direction and its ends are connected to a battery, rheostat and a tapping key. When the key is open i.e., no current flows in the conductor, the needle points in N-S direction. As the key is pressed and a current passes in the conductor, the needle deflects. This shows that a magnetic field Exists around a current carrying conductor.
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