# Homework Help: Average force of a molecule

1. Apr 21, 2010

### cdotter

1. The problem statement, all variables and given/known data
...Suppose an oxygen molecule (m=5.32E-26 kg) traveling at this speed ($\nu_{rms}=484 m/s$) bounces back and forth between opposite sides of a cubical vessel 0.10 m on a side. What is the average force the molecule exerts on one of the walls of the container? (Assume that the molecule's velocity is perpendicular to the two sides that it strikes.)

2. Relevant equations
$F=\frac{dp}{dt}$

3. The attempt at a solution
I can't remember how to do this, even after looking through my notes.

2. Apr 21, 2010

### cdotter

Nevermind, I found it.

$$\frac{dP_x}{dt}=\frac{NAMv_x^2}{V}$$