Question

fig 8.1 shows a bar magnet suspended by a spring over a coil. This coil is connected to a sensitive centre-zero millivoltmeter answer

Answer 1

The magnet creates a magnetic field. When the field lines cross a coil, the field generates electromotive force that creates current if the coil circuit is closed. The millivolmeter will only show reading if the magnet moves with regard to the coil. If it is stationary above the coil, the readings will be 0.