Suppose Sumana forgets to move the switch of her lifting electromagnet model to OFF position (in introduction story) Class 8

Suppose Sumana forgets to move the switch of her lifting electromagnet model to OFF position (in introduction story) Class 8

Suppose Sumana forgets to move the switch of her lifting electromagnet model to OFF position (in introduction story). After some time, the iron nail no longer picks up the iron paper clips, but the wire wrapped around the iron nail is still warm. Why did the lifting electromagnet stop lifting the clips? Give possible reasons. Class 8

Answer:

A conducting coil becomes a magnet only when the electric current is flowing through it. When Sumana forgets to switch off, the battery gets drained and the flow of electric current is stopped or weakened. So, the coil loses its magnetic effect. The heating effect of electric current converts a part of the electric energy to heat energy. This heat energy makes the current-carrying wire warm. When the current stops flowing the heating effect of the electric current stops, but the wire that has become warm takes some time before cooling to the normal temperature.