Why does the cord of an electric heater not glow while the heating element does ?
The heating element of an electric heater is made up of alloys.
Alloys have very high resistance, so when the current passes through the alloy, it blocks the current and doesn’t let it pass through it.
Thus, the heating element becomes hot and glows red.
On the other hand, the cords are made up of good conductors like copper.
They have low resistance, and do not produce much heat when same amount of current is passed through it.
Hence, the cord does not glow.