Question

Explain Planck's quantum theory.

Answer 1

1. Electromagnetic waves were considered to be the only waves in the Newtonian era.
2. This explained phenomena like reflection and reflection but couldn't explain phenomena like the photoelectric effect.
3. Max Planck was the first to propose that EM waves are made up of matter-like particles called quanta.
4. He also gave a formula giving the energy of quanta in relation to the frequency of the wave.
5. $E=hv$ Where E is the energy of a photon v is the frequency of the wave and h is the Plank constant.
6. The plank constant has value $h=6.625\times {10}^{-34}Js$.
7. Planck's quantum theory helped to explain the particle-like nature of light.
8. This was later used by Einstein to explain the photoelectric effect.