Chapter 8 : Let us answer these (Page-171)

Q1. Why does the connecting wires i.e. the cord of an electric iron or an electric heater not glow while the heating element glow?

Ans: - The resistance of connecting cord of heating is very low. Therefore, it produces negligible heat. Hence not glow. The resistance of heating coil is very high. Therefore, heat is generated resulting glowing.

Q2. How will you connect the two resistors of 10ohm each and two resistot of 4ohm each to get the equvalent resistence of 7ohm?
Ans:

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