A copper wire iis stretched to make it `0.1%` longer. What is the percentage change in its resistance?

A copper wire iis stretched to make it `0.1%` longer. What is the perc

1.	A copper wire iis stretched to make it `0.1%` longer. What is the percentage change in its resistance?
Answer» `R=rho 1/A=(rhol)/(V/l)` (`V=` volume of wire) `=(rhol^2)/V` `:. R propl^2` (`rho "and" V=` constant) For small percentage change % change `R=2(%"change in" l)=2(0.1%)=0.2%` Since `Rpropl^2`, with increase in the value of `l`, resistance will also increase.

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A copper wire iis stretched to make it `0.1%` longer. What is the percentage change in its resistance?

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