The number density of free electrons in copper is nearly 8 × 10 28 m - 3 . A copper wire has its area of cross-section = 2 × 10 - 6 m 2 and is carrying a current of 3 . 2 A . The drift speed of the electrons is _____ × 10 - 6 m s - 1 .

Step-by-step solution

The formula to calculate the current through any conductor is given by I = n A e v d       . . . 1 Substitute the values of the given parameters into equation (1) and solve to calculate the required drift velocity of the electrons. 3 . 2 = 8 × 10 28 × 2 × 10 - 6 × 1 . 6 × 10 - 19 × v d ⇒ v d = 3 . 2 16 × 1 . 6 × 1000   m   s - 1 = 125 × 10 - 6   m   s - 1