1# Light and matter 2 3## Photoelectric effect 4 5### Planck's equation 6 7$$E=hf$$ 8 9where 10$E$ is energy of a quantum of light (J) 11$f$ is frequency of EM radiation 12$h$ is Planck's constant ($6.63 \times 10^{-34}\operatorname{J s}$) 13 14 15### Electron diffraction patterns 16 17$$W=qV$$ 18 19(work for accelerating electon of charge $q$ with voltage $V$) 20 21$$\lambda = {h \over mv}$$ 22 23(de Broglie's equation) 24 25Solving wavelength of electrons from gun: 261. 27 28774 abc melbourne