Explanation: S waves behave like ripples of water .
What motion do S waves have?
S waves shake the ground in a shearing, or crosswise, motion that is perpendicular to the direction of travel. These are the shake waves that move the ground up and down or from side to side. S waves are called secondary waves because they always arrive after P waves at seismic recording stations.
What is an S wave similar to?
Secondary waves, or S waves, are slower than P waves. The motion of secondary waves is perpendicular to the direction of the wave travel, similar to the motion of vigorously shaking a rope (SF Fig. 7.1 B).