Question

A copper wire of length 100 metres has a resistance of 5 ohms. Calculate the diameter of
the wire, given that the resistivity of copper is 1.7 x 10-6 ohm-m. (Ans.: 0.65 * 10–³ m)​

Answer 1

Answer:

Consider The resistivity of copper ρ = 1.7 × 10−8 Ω-m

Given length of wire l = 100 m

Resistance R = 5 Ω

Using R = ρl/A

A = ρl/R

A = 1.7 × 10−8 x 100/5

A = 34 x 10−8 m2

πr2 = A = 34 x 10−8 m2

r2 = 10.8 x 10-8 m2

r = 3.28 x 10-4 m

Thus diameter is 2r = 6.56 x 10-4 m

Hope this information will clear your doubts about topic.

Answer 2

Explanation:

answer

. I hope it helps.