Question

a conductivity of material of length -l1 and area- A2 streched to double it's length what is new resistance​

Answer 1

R1=1/C1=PL1/A1

When length is doubled the area reduces to half of it's initial value

R2= pL1×2×2/A1

R2=4 pL1/A1

R2=4 R1

I hope this helps ( ╹▽╹ )