Question

Calculate the resistance of a wire which has a uniform diameter 10.74mm and a length of 70.63cm if the resistivity is known to be 0.00092 ohm.m. Give your answer in units of Ohms up to 3 decimals. Take pi as 3.1416

Answer 1

7.173Ω

Step-by-step explanation:

R = ρ(L/A)

ρ = 0.00092 Ω

convert L and D to meters so all the units are consistent

L = 70.63 cm = 0.7063 m

D = 10.74 mm = 0.01074 m

r = D/2 = 0.01074 m / 2 = 0.00537 m

A = πr² = (3.1416)(0.00537 m)² = 9.06x10⁻⁵ m²

R = (0.00092Ω)((0.7063 m)/( 9.06x10⁻⁵ m²) = 7.173Ω