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Question
When the free ends of a tester are dipped into a solution, the magnetic needle shows deflection. Can you explain the reason?
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Solution
When the free ends of a tester are dipped in a solution, the magnetic needle deflects. This happens because electric current is flowing through the tester. When its free ends are dipped in the solution, due to the flow of this electric current, a magnetic effect is generated in the magnetic needle, as a result of which the magnetic needle starts deflecting.
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