Question

The resistance of a bulb filament is 100Ω at a temperature of 100∘C. If its temperature coefficient of resistance be 0.005per∘C its resistance will become 200Ω at a temperature of

Answer 1

If a wire has a resistance R, at a temperature To, then its resistance R at a temperature ... (T - T.), where a is the temperature coefficient of resistance of the material of the wire. ... Dividing by e = 1.6 x 10-19 C, the magnitude of charge on a single electron, we get number of electrons per second = 0.7/(1.6 x 10-19)= 4.4 x 1018.