For each of these videos click and drag your mouse curser from left to right on the video screen - this will play the video forward. Click and drag from right to left and the video will play backwards.

Animation 1. Two sine peaks

Animation 2. One sine peak and one sine trough

Animation 3.One sine peak and one triangular peak

Animation 4.One sine peak and one triangular trough

Animation 5.One sine peak and one square peak

Animation 6.One sine peak and one square trough

Slinky 1. Meeting of two peaks

Slinky 2. Meeting of a peak and a trough

Slinky 3. A peak meeting a trough with the original waveforms shown as reference.

Slinky 4. Two peaks of different wavelength meeting.