https://tr.khanacademy.org/science/ap-physics-2/x0e2f5a2c:waves-sound-and-physical-optics 2026-03-27T05:00:56.939192419Z Waves, sound, and physical optics Investigate the behavior of waves, including sound waves. Learn ways to quantify a wave, including amplitude, wavelength, period, frequency, and wave speed, and how light can be modeled as a wave. Explore diffraction and interference, polarization, the Doppler effect, and thin-film interference. unit