Question 412: Current Electricity

Question

If a wire is stretched to make it $0.1\% $ longer, its resistance will:

Accepted Answer

Resistance of wire
$R = {{ho l} \over A} = {{ho {l^2}} \over C}$ (where $Al=C$ )
$	herefore$ Fractional charge in resistance
${{\Delta R} \over R} = 2{{\Delta l} \over l}$
$	herefore$ Resistance will increase by $0.2\% $

Answer

increase by $0.2\% $

Answer

decrease by $0.2\% $

Answer

decrease by $0.05\% $

Answer

increase by $0.05\% $

Current Electricity

If a wire is stretched to make it 0.1\% longer, its resistance will:

Choose the correct answer: