Calculate the cross sectional area of an aluminum wire of resistance 520 O, length 24 m, and resistivity 2.65 × 10–8 O·m.

Question

Calculate the cross sectional area of an aluminum wire of resistance 520 Ω, length 24 m, and resistivity 2.65 × 10–8 Ω·m.

Answer 1

The formula that most memorize is R = p (L/A).  What literal equation do you get when you solve for Area, A ?

 

Into this literal equation, Sub, 520 ohms for R, 24 m for L and using rho = 2.65 x 10^-9 (ohm)(m), the answer comes up

A = 1.22 x 10^-9 m².