Question

how Compton Effects justify particle nature of light

Answer 1

Compton scattering is an inelastic scattering of a photon by a free charged particle, usually an electron. It results in a decrease in energy (increase in wavelength) of the photon (which may be an X-ray or gamma ray photon), called the Compton effect. Part of the energy of the photon is transferred to the scattering electron
so as photo electric effect it is also very rapid which can not be possible if light was a wave hence it justify particle nature of light

Answer 2

thank you Raj