Ripples from a dropped stone
Drop a stone in a pond and rings spread outward while the water itself just bobs in place — the wave carries energy, not water. Sound does the same through air, which is how a shout reaches your friend across the yard.
Wiggles that carry energy
A wave carries energy without carrying matter along with it. Its amplitude is the height of the wiggle; its frequency is how many wiggles pass each second. For sound, higher frequency means higher pitch, and larger amplitude means louder.
Simulation · Wave: amplitude & frequency
Raise the amplitude to make a 'louder' wave; raise the frequency to make a higher 'pitch'.
Lab · Pitch vs. loudness
- Increase the frequency and watch the wiggles bunch up.
- Reset, then increase the amplitude.
- Note which control changes height and which changes how many waves fit.
What you should see: Frequency controls how many waves fit (pitch); amplitude controls their height (loudness).