Shear waves and shocks in soft solids.

We study the motion of a sphere falling through soft viscoelastic materials when the time scale of the motion is short compared to the elastic relaxation time of the material. We observe shocks generated by the passage of the sphere at Mach numbers greater than 1. The sphere can undergo oscillations before reaching a steady terminal speed, and we show that these oscillations have the same frequency as the shear wave associated with the shock.