Physics
Doppler Effect
Move a sound source and an observer, change the speed of sound and the wind, and watch the observed frequency shift — all the way to a supersonic Mach cone.
Simulations for High school
Connect equations to what you can see and change.
PhysicsEngineering
Wave Propagation Through Materials
Send a sound or electromagnetic wave into a slab of water, glass, concrete, metal or lead and see how much is reflected, absorbed and transmitted.