What length of a certain metal wire of diameter 0.15 mm is needed for the wire to have a resistance of 15 Ω? The resistivity of this metal is 1.68 × 10^-8 Ω ∙ m.

Question

Quizplus · Accepted Answer

The resistance R of a wire is given by the formula R = ρL/A, where ρ is the resistivity, L is the length, and A is the cross-sectional area. The area A for a wire of diameter d is π(d/2)^2. Substituting the given values and solving for L gives approximately 16 m.

What Length of a Certain Metal Wire of Diameter 0