# Waves and Vibrations

See

- Differential Equations

moving shapes $psi(x - vt)$ is a shape moving to the right. $cos(x - vt)$ $cos(kx - \omega t)$

$e^{-(x - vt)^2}$ gaussian wave packets

$\omega = c k$ influence moving far even when the medium doesnâ€™t

from cosines to exponentials

ocean waves

geometric wavefronts

phase velocity group velocity

ball and chain model
wave equation `\nabla^2 \psi = \frac{1}{v^2} \partial_t^2 \psi`

wave matching wavevectors

Periodic media - brillouin book French book

Waves in scattering media

Localizaion

# Interference

Double slit Single slit

The semiclassical approximation. Distances give phase

Pipes Thin films

# SHO

We did discuss this some elsewhere.

# Acoustics

AP French book https://farside.ph.utexas.edu/teaching/315/315.html Oscillations and Waves