5.4 Niels Bohr used the quantum hypothesis to explain atomic spectra Max Planck's quantum hypothesis(量子假设): a beam of light energy is not the continuous stream of energy, but consists of small, discrete packets of energy. Each packet was called a quantum. In 1905. Einstein recognized that these quanta of light behave like particles. Each quantum was called a photon f). light behaves as both a wave ana a particle Totally reflecting mirror Flash lamp aser beam Partially reflecting mirror5.4 Niels Bohr used the quantum hypothesis to explain atomic spectra Max Planck’s quantum hypothesis (量子假设): a beam of light energy is not the continuous stream of energy, but consists of small, discrete packets of energy. Each packet was called a quantum. In 1905, Einstein recognized that these quanta of light behave like particles. Each quantum was called a photon (光子). Light behaves as both a wave and a particle