Question

A wire of resistivity "s" is stretched to double it's length. Find its new resistance and resistivity

Answer 1

if the length of the wire is increased the resistance increases.The resistant increases there will be increase in temperature so there is a increase in resistivity.

rho= s

l= 2l

rho=R × A/l

R=rho × l/A

area of cylinder=2πr²

R=s×2l/2πr²