Angle φ is set by the angle that the balls collide at.
Angle θ depends on φ and balls masses.
| Collisions between hard spheres |
| When two hard spheres collide they only
touch at one point. This point lies on a line joining the centres of the
spheres. Try this with two coins if you don't get it! If one ball is moving
(blue) and hits a stationary ball (red) then the balls will exert equal
size but opposite direction forces upon each other (Newton's third law).
These forces act along the line joining the centres of the spheres. The
blue ball will experience a force that makes it decelerate (Newton's first
law) and the red ball will be accelerated by the equal but opposite force
that it experiences.
Angle θ depends on φ and balls masses. |
