do s waves move more rapidly than p waves?
S waves arise from forces trying to change the shape of of an object. As the diagram shows, shear waves are the result of the medium's resistance to this sort of deformation. There are some important concept to keep in mind when we use seismic waves to investigate the structure of the interior of the Earth. The first is that P waves travel faster than S waves. This is the reason they are referred to as primary waves, as they are the first seismic waves to arrive at a seismic station. The second is that seismic waves travel faster through media which offer more resistance to that type of deformation.