Protons do not move out of the nucleus of atoms although they repel each other.
Remember that protons are particles with positive charge and they held together in the nucleus of the atom which is a tiny tiny region. As you know, like charges repel each other, which means that the protons exert a repulsion force.
Ground water keept the ground at a stable level when it is gone the cavern it was in has no support and is at risk of callaps
find acceleration force divided by Mass
a=f/m
