# Homework Help: Physical Chemistry- Maxwell Boltzmann Distribution

1. Sep 26, 2010

### sdoyle1

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

Use the maxwell boltzmann distribution to derive an expression for <v^3>

2. Relevant equations
<v>=(8RT/piM)^1/2

3. The attempt at a solution
I know that you have to integrate from 0 to infinity v^3p(v)dv.. but I don't really know how to integrate this. I just need to find a general integral then I can look it up in the handbook for chemistry and physics...

2. Sep 26, 2010

### vela

Staff Emeritus
Use the substitution u=v2 (maybe throw in the constants while you're at it), and you'll have an integral in the form of the gamma function.