If the area of a conductor doubled and also the length, what would be the change in the new resistance?

Expert Answers

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The resistance of a conductor is computed using the formula:

`R = rho * L/A`


`rho` is the resistivity of the material

L is the length of the conductor, and

A is the cross-sectional area of the conductor.

For this problem, let the length of the conductor be y and its cross-sectional area be x. Applying the formula above, the resistance of the conductor will be:

`R =rho * y/x`

When the length and cross-sectional area of the conductor is doubled, the new resistance will be:

`R_(n ew) = rho*(2y)/(2x)`

And it simplifies to

`R_(n ew) = rho * y/x`

Notice that the R_new is the same with the original R. 

Therefore, when the length and cross-sectional area of the conductor are increased by the same factor, there is no change in resistance.

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