Question 654: Current Electricity

Question

The resistance of a wire is 'R' ohm. If it is melted and stretched to 'n' times its original length. its new resistance will be

Accepted Answer

Resistance $$R = \rho l/A$$
$$l' = nl$$ and $$A' = {A \over n},R' = {{\rho l} \over {A'}}$$
$$R' = {{\rho nl} \over {A/n}} = {{\rho l} \over A}{n^2}$$
$$R' = R{n^2}$$

Answer

$${R \over n}$$

Answer

n2R

Answer

$${R \over {{n^2}}}$$

Answer

nR

Current Electricity

The resistance of a wire is 'R' ohm. If it is melted and stretched to 'n' times its original length. its new resistance will be

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