# Homework Help: How do I find the average velocity of an electron?

1. Jan 27, 2012

### chueco

1. The problem statement, all variables and given/known data

A current of 1600A exists in a rectangular (0.4-by-16cm) bus bar. the current is due to free electrons flowing the wire at an average velocity of v meters/second. If the concentration of free electrons is 10^29 electrons per cubic meter and if they are uniformly dispersed throughout the wire, then what is the average velocity of an electron?

2. Relevant equations

I don't know where to start.

3. The attempt at a solution

2. Jan 27, 2012

### Staff: Mentor

Welcome to the PF.

What is the equation that relates current I to the flow of charge Q per unit time T?

And if you start with that equation, then you need to take into account how much charge there is per electron, and how many electrons are flowing....

The numbers you are given are useful, because they tell you the density of the electrons, and the cross-sectional area of the conductor...