A 10 gauge copper wire carries a current of 20 A. Assuming one free electron per copper atom, calculate the magnitude of the drift velocity of the electrons.

Complete Question

A 10 gauge copper wire carries a current of 20 A. Assuming one free electron per copper atom, calculate the drift velocity of the electrons. (The cross-sectional area of a 10-gauge wire is 5.261 mm2.) mm/s

The drift velocity is

Explanation:

From the question we are told that

    The current on the copper is  

     The cross-sectional area is  

The number of copper atom in the wire is  mathematically evaluated

Where is the density of copper with a value

          is the Avogadro's number with a value

         Z  is the molar mass of copper with a value  

So

Given the 1 atom is equivalent to 1 free electron then the number of free electron is  

The current through the wire is mathematically represented as

substituting values

=>    

the answer is a 3.8cm

explanation:

photocells convert light energy to electricity