This program simulates the physics of waves on a string. Drag one of the blue bubbles up and down to start a wave. (If the string wanders off the page, click Reset.)

The mass density controls how heavy the string is. A larger value makes the wave propagate more slowly.

The tension controls how stretchy the string is. Smaller values make the wave spread outward into ripples.

SECRET TIP: You can use two fingers to hold both ends of the string and wiggle it to make standing waves!