287

Introduction

This section introduces waves and wave motion.

What do these things have in common?

●the sounds we hear

●the warmth we feel from the sun

●the motion of electrons inside atoms.

Answer: we can analyse them all in the same way—by using the language and physics of waves.

There are four main classes of waves: mechanical waves (such as sound and waves on strings), electromagnetic waves (such as light), gravitational waves, and matter waves (such as electron motion in atoms).