Question

What will be the effect on resistance of wire if area of cross section becomes 4times and length is made half?? Please explain its urgent

Answer 1

if u increase the cross section than resistance decreased as i u r saying that 4times the area it means half will be resistance and if length is made 1/2than than resistance becomes i/2


because resistance is inversely proportional to its area of cross section and directly proportional to length

Answer 2

If u will put the new value in the formula of resistance R=rho ×l/A
here rho is constant
if new length=l/2 and new area =4A than
R=rho×l/2×4A
new R =R/8