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Question
When current is switched ‘on’ in a room heater, it ______.
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Solution
When current is switched ‘on’ in a room heater, it becomes red hot and emits heat.
Explanation:
The working of a room heater is based on the heating effect of electric current, which converts electrical energy into heat energy to warm the room.
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Your teacher has shown you the following activity.

Activity: Teacher has wound a long insulated piece of wire around an iron nail in the form of a coil. Free ends of the wire are connected to a cell through a switch as shown in the following figure. The current is switched on and some pins are placed near the ends of the nail.
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