Question
Using the results of Example 20.3, find the drift velocity in a copper wire of twice the diameter and carrying 20.0 A.

#### Example 20.3

Calculate the drift velocity of electrons in a 12-gauge copper wire (which has a diameter of 2.053 mm) carrying a 20.0-A current, given that there is one free electron per copper atom. (Household wiring often contains 12-gauge copper wire, and the maximum current allowed in such wire is usually 20 A.) The density of copper is $8.80 \times 10^3 \textrm{ kg/m}^3$ .

$-0.113 \textrm{ mm/s}$

Solution Video