If the length of a wire is increased by 20% keeping its volume constant. what will be the % change in heat produced when connected across same potential difference. explain

decreases by 30.55%

Explanation:

Given

length of wire is increased by 20 % keeping volume constant

Let the length of wire be L and its area of cross section be A

Thus new length=1.2 L

Volume is constant

A'=0.833 A

and resistance is given by

where =resistivity

New resistance

R'=1.44 R

heat produced for same potential

% change in heat

=30.55 decreases

ι вєℓιєνє ιт ιѕ тнє fιяѕт ¢нσι¢є(α.)

нє ѕнσυℓ∂ ѕмιℓє ρσℓιтℓу αи∂ ѕρєαк тσ тнє ρєяѕσи ωнσ ιѕ ιитєяяυριиg αfтєя тнє ∂ιѕ¢υѕѕισи

нσρє ι ¢συℓ∂ нєℓρ.