Question

Two wires of Same material have length in ratio 1:2. the ratio of specific resistance will be

Answer 1

we know that ,the wires are made up of same material , hence resistivity will be same , and as it is a series combination so current will be same .

Here, we have L1 : L2 = 1:2

and, d1: d2= 2:3 (YOU NOT MENTIONED )

therefore , with the help of ohms law

v = IR
where, v = potential difference
I= current
and R= resistance.

also , R=p ౹ / A

so, v = ౹ p౹ /A

here, p= resistivity of conductor, l= length of conductor, A = area of cross section of conductor.

For the two wires,

therefore, the lengths are l1 , l2
for the cross section areas A1, A2
and for the diameters D1, D2


now follow the picture,

Answer 2

if wires form with same material then , specific resistance is same , bcoz this depends upon only material . not length of wire