# Escape probability of a particle in a sphere

1. Apr 5, 2012

### anon_man

how can we use statistical mechanics to find the probability of a particle inside a sphere to escape through a hole on the surface (no potential energy) ? any ideas ??

2. Apr 11, 2012

### gomunkul51

Look up Brownian Motion.

Cheers.

Roman.

3. Apr 11, 2012

### Khashishi

I don't think this is statistical mechanics. Just compare the area of the hole to the area of the sphere, and consider how fast the particle is moving.

4. Apr 12, 2012

### haruspex

Probability of particle traveling at speed U escaping from volume V through aperture area A in time period dT will be proportional to U.A.dT/V. Don't know what the multiplicative constant would be - perhaps depends on geometry.