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Class 10 Science Medium Mcq English Medium

Why does the cord (connecting wire) of an electric heater not glow, while the heating element does?

Question
Why does the cord (connecting wire) of an electric heater not glow, while the heating element does?
The cord carries less current than the element
The cord has much lower resistance than the heating element, so it dissipates much less heat
The cord is made of an insulator
The cord is cooled by a fan
Answer
The cord has much lower resistance than the heating element, so it dissipates much less heat
Detailed Explanation
Since both carry the same current in series, and heat H = I^2Rt, the cord's much lower resistance means it produces far less heat and does not glow.
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