Question

Aluminum wire has a radius 0.25 mm and a length of 75m. If the resistance of the wire is 10 ohm. Calculate the resistivity of aluminium

Answer 1

Answer:

r= 0.25*10^3 m, l= 75 m, R= 10ohm

Area of Wire:

=πr^2

= (0.25*10^3)^2 *π

= 0.25*0.25*10^6*π

If we take π=3.14

= 0.25*0.25*3.14*10^6

= 0.0625*3.14*10^6

= 0.19625*10^6

R = pl/a

p = R*a/l

p = 10 * 0.19625*10^6/75

p = 0.19625*10^7/75

p = 0.025* 10^7