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

Options

A. nR
B. `(R)/(n)`
C. `n^(2)R`
D. `(R)/(n^(2))`

Answer

C

Explanation

`(R_(2))/(R_(1))=(l_(2)^(2))/(l_(1)^(2))`
`=(n^(2)l_(1)^(2))/(l_(1)^(2))`
`(R_(2))/(R_(1))=n^(2)`
` R_(1)=n^(2)R_(1)`