Question

you are provided with a magnetic compass an empty match box a battery of two cells and connecting wires using these how will you make a tester for testing an electric circuit

Answer 1

Make a coil of at least 20 turns using the wires. Then place the compass inside the coil such that its face is towards the wall of the cylinder(coil). Then to test current in a circuit, connect the ends of the wire of coil in series with the circuit. If current is present, the compass will show deflection. Else nothing will happen. I don't know how match box will be used. The battery must be given for making a circuit which has to be tested.