Question

What is the resistance of 1.0 m of a solid cylindrical metal cable having a diameter of 0.40 inches and a resistivity of 1.68 × 10-8 ω • m?

Answer 1

0.00021 Ω

Explanation:

R = ρℓ/A

Resistivity: ρ = 1.68×10 ̄ ⁸ Ωm

Length: ℓ = 1.0 m

Area: A = π*radius² = π * ( (0.40inch * 0.0254m/inch) / 2 )² = 8.1×10 ̄ ⁵ m²

Answer 2

Hi there!

So here we have

redistivity =1.68/100000000W.m

diameter =0.40in

So its going to equal 0.01016m

The length =1m

The resistance =?

To find it you multiply the resistance times the area and length

redistivity =resistance×area/lenght

So given by the choices the answer is B.

A) 0.00012 Ω

B) 0.00021 Ω

C) 0.0012 Ω

D) 0.0021 Ω