Question

Two wires A and B of the same material and having same length, have their cross-sectional area in the ratio 1:6. What would be the ratio of heat produced in these wires when same voltage is applied across each?

Answer 1

H = \(\frac{V^2t}{R}\)

= V²t x \(\frac{A}{ρl}\);

A = area of cross-section

∴ H∝ A

Or, \(\frac{H_1}{H_2}\) = \(\frac{A_1}{A_2}\) = \(\frac{1}{6}\)