- How does a force that is proportional to displacement result in an oscillation?
- Are all oscillations simple harmonic?
- What is the connection between oscillations and waves?
- Are waves really made of an infinite number of wavelets?

### Mass on a spring

Another physics book classic, the mass hanging on a spring. A bit easier to analyse than a pendulum but not as easy as the mass on a spring in space. Quite obvious that the acceleration is proportional to displacement, once you realise that SHM follows.

### Light

To understand the propagation of electromagnetic waves you need to have studied the next section on electromagnetism. However it is enough to use what we know about other waves to understand the wave nature of light.

### Waves

If you line up a lot of pendulums and start them swinging at different times you get a wave pattern, this leads to our mathematical model of all waves.

### Waves in a slinky spring

This page isn't finished (started) yet but a slinky is one of those springs that climbs down the stairs.

### Waves in a string

It is easy to observe the wave motion in a string but it doesn´t tell the whole story of wave properties. A string wave can't diffract or interfere. Sometimes simple explanations cause misunderstandings. Here a string wave is polarised by a narrow slit.

### Phase

A juggler may not understand the mathematical representation of phase but the are using the effect as they throw balls in the air at different times. It is important to understand the concept of phase before starting the waves section.