Answer to Question #350949 in Physics for Lemy

Question

5 m wire made of gold ( ρgold = 2.4 x 10−8 ) has a cross-sectional area of 2 mm.

Calculate the voltage if a 32 A current runs through the wire.

Answer 1

The Ohm's law says

$$I=\frac{V}{R}$$

Hence, the voltage

$$V=IR=I\rho\frac{l}{A}$$

$$V=32*2.4*10^{-8}*\frac{5}{3.14*0.001^2}=1.2\:\rm V$$