Now select the light bulb as the current indicator in the circuit. Move the magnet back and forth through the coil at different rates and observe the variation of the brightness of the bulb. According to Faraday’s law of induction, the rate of change of magnetic flux through the coil is proportional to the voltage induced voltage in the coil. Why does the brightness of the bulb change when you move the magnet through the coil at different rates? Explain your answer with Faraday’s law and electrical

The magnitude of induced voltage varies with rate of change of magnetic field.

Explanation:

The experiment aims to demonstrate the principle of electromagnetic induction as shown by Michael Faraday. The intensity of the bulb is a physical indicator of the magnitude of induced voltage. A simple statement of Faraday's law of electromagnetic induction is that the induced voltage in a circuit is proportional to the rate of change over time of the magnetic flux through that circuit. This implies that, the faster the magnetic field changes, the greater will be the voltage in the circuit.

Moving the magnet at different rates implies changing the magnetic field hence the magnitude of induced voltage also changes accordingly. This change is indicated by changes in the brightness of the light bulb.