ABSTRACT
Vibrations, sound, and light involve the propagation of waves. In the case of vibrations, these waves carry information about small changes in the shape of an elastic body. Vibrations are elastic waves. Our sense of touch can be used to track these elastic changes in shape as a function of time. Sound is the propagation of small changes in pressure through a fluid and our ears may be used to track these waves. Light is the propagation of small disturbances in electric and magnetic fields and we can use our eyes to track these changes. But for certain frequencies our senses are no longer adequate and specialized instruments are needed to sense vibrations, sound, and light.
