Both the object and the particles can move?

[Hootenanny]

Consider a sealed box with a set number of particles in, plus an object which has a massive volume compared to the other particles. In which case will there be more particle - object collisions?

(a)If the the object is static and all particles move.
(b)Both the object and the particles can move?

Any input would be appreciated

 

[arunbg]

If all velocities are equal(both object and particles) and in random directions and consequently all particles are distributed randomly, one would expect both cases to give almost equal no of collisions.
Motion has little effect since averaged over time, these effects should cancel.Also no particular position is preferred.

 

[Hootenanny]

Thanx arunbg