1. Introduction to Waves
You may remember most of this information from GCSE but this covers some of the wave properties you need to understand and introduces the jelly baby wave machine for the first time.
2. Wavelength, Periods, Amplitude and Phase Difference
You must understand this key wave terminology to fully grasp this fascinating subject. Wavelength, time period, amplitude and phase difference are explained using jelly babies.
3. The Wave Equation
Very furry lambs and an analogy with train carriages explain the derivation of this important wave equation.
4. Wave Properties
Both transverse and longitudinal waves share similar properties that you must be familiar with to understand further topics like lenses and interference: but only transverse waves can be polarised.
The App running is called Ripple Free by Paul Falstad.