Particle collision

[asdf1]

why does an alpha particle have the smallest distance to an atom if it aprroaches the nucleus head on?

 

[jtbell]

Because if the alpha comes in head on, it can convert all of its kinetic energy to potential energy, coming to a complete stop momentarily before rebounding in the opposite direction. If it doesn't come in head on, it never comes to a complete stop, so its maximum potential energy is smaller.

 

[asdf1]

oh right!!!
thanks!!! :)