/sci/ - Science & Math

Hello /sci/, I want to calculate how many interactions occur per second in my system.
Imagine a spherical space (red) filled with a fixed number of spherical objects (not in the graphic because they are too small).
The objects have a mean velocity and a density distribution.
Let's just assume the density goes with 1/r.

Now I want to know how many objects interact (in this context it just means enter) with a cone like space (green) per second.