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Question
Why does the filament of an electric bulb in an electric circuit get white-hot, but not the connecting wires?
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Solution
The filament of an electric bulb is made up of tungsten having high resistance. Due to its high resistance, on passing an electric current through it, electrical energy changes into heat energy. So much heat is produced that filament of bulb becomes white-hot and gives light.
The resistance of connecting wires is very low and hence the connecting wires do not get heated.
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