Question

Ek of A copper wire of resistance is stretched till its length is increased 2n times of its original length?what will be its new resistance

Answer 1

heya dear your answer is here
______
original resistance=R ohm
ORIGINAL LENGTH=l
cross section area=A
resistivity=rho
R =rho×l÷A
rho=RA÷l

so now
new length=2l

new resistance= rho × l ÷ 2A
= (RA÷l)×(l÷2A)
= R/2 ohm