A light metal disc on the top of an electromagnet is thrown up as the current is switched on. Why? Give reason.

Take a strong cylindrical electromagnet connected to AC source and place a light metallic disc at the top of it. When the current is switched 'on', the disc is thrown up in the air. a. Why does the disc go up? b. How is the repulsive force produced?

Take a strong cyclindrial electromagnet connected to AC source and place a light metalic disc at the top is it. When the current is switched on , the disc is throw up in the air. Why does the disc go up?

A metal disc is winging freely between the poles of an electromagnet, as shown in the figure. When the electromagnet is switched on, the disc comes to rest after a few oscillations. Explain why eddy currents are induced in the metal disc.

A metal disc is winging freely between the poles of an electromagnet, as shown in the figure. When the electromagnet is switched on, the disc comes to rest after a few oscillations. Use Faraday's law of electromagnetic induction to explain why an e.m.f. is induced in the disc.

Why do birds fly off high tension when current is switched on?

Sparking occurs in the switches when light is put off. Given reason.

Consider a metal ring kept on the top of a fixed solenoid (say on a cardboard) (Fig. EP 6.14). The centre of the ring coincides with the axis of the solenoid. If the current is suddenly switched on, the metal ring jumps up. Explain.