The wired in Figure1are all made of the same materialthe len

The wired in Figure1are all made of the same material,the length and radius of each wire is noted. Rank in order, from largest to smallest, the resistance R_1 to R_s of these wires Rank from largest to smallest. To rank them as equivalent overlap them.

Solution

Resistance = resistivity x L / A

as all are made of same material hence resistivity will be same.

for 1:

R1 = rho * L / (pi r^2) = (rho L) / (pi r^2)

for 2:

R2 = rho*L / (pi (2r)^2 )   = (rho L / pi r^2) / 4

for 3:

R3 = rho*2L / (pi (2r)^2 )   = (rho L / pi r^2) / 2

for 4:

R4 = rho*2L / (pi (r)^2 )   = 2 (rho L / pi r^2)

for 5:

R5 = rho*4L / (pi (2r)^2 )   = (rho L / pi r^2)

largest to smallest:

R4 > R5 = R1 > R3 > R2