Ripple Effect

When were at Lake Martin this weekend, we were playing with Mr Big (the family's dog). We were throwing rocks into the water for him to fetch them.  I was aware that when a rock hit the water, it created many ripples instead of just one ripple or wave.  This is because when the rock hits the water, it disturbs the water's equilibrium.  The water then starts moving like a spring: it oscillates.  Due to gravity, the stone falls and makes the height of the water decrease.  The water then oscillates periodically up and down trying to restore its equilibrium.  In this type of movement, we can observe changes in the kinetic and potential energies in the water. This movement will eventually come to a stop when the energy is lost to the viscosity of the water, also friction forces slow the movement down and make it stop eventually.