Question

When free ends of tester is dipped into a solution the magnetic needle show reflection?why

Answer 1

Electric current produces magnetic effect which causes deflection of the magnetic needle of a compass. So, when the free ends of a tester are dipped into a solution which is a good conductor of electricity, the needle shows deflection

Answer 2

Answer:

The deflection in the compass needle shows that current is flowing through the wounded wire and hence, through the circuit. The circuit is complete since free ends of the tester are dipped in a solution. The solution is certainly a conducting solution. This is the reason why the compass needle shows a deflection.