# Properties of Photons

The phenomenon of photoelectric effect led to the conclusion that light is in the form of photons. The emission of electrons from the surface of metals when it is irradiated with electromagnetic radiation is called the photoelectric effect. Photons are considered as the fundamental particles of light. They have unique properties which enable them to act as both particles and waves.

## 15 Important Properties of Photons

Properties of photons are listed below.

Property 1: The energy of a photon is given as $E = h\nu$, here $\nu$ is the frequency and h is the Planck’s constant.

Property 2: We know that speed of light is given by c = 3 x 108 m/s. Therefore, the speed of the photon is also equal to c = 3 x 108 m/s.

Property 3: The rest mass of the photon is zero.

Property 4: Photons are stable particles.

Property 5: They do not have any electric charge.

Property 6: Irrespective of the intensity of the radiation, every photon of frequency $\nu$ has the momentum,

$p =h\nu/c$ and energy $E = h\nu$

Property 7: The dynamic mass of the photon is m = E/c2, where E is the energy of the photon.

Property 8: Photons can interact with other particles like electrons, which can be seen in Compton effect.

Property 9: Photons can be created or destroyed when the radiation is emitted or absorbed.

Property 10: During photon-electron collision, the momentum and total energy are conserved.

Property 11: Photons do not decay on their own.

Property 12: The energy possessed by the photon can be transferred to other particles when it interacts with other particles.

Property 13: Photons are not affected by the magnetic field and electric field.

Property 14: Photons only exist as moving particles.

Property 15: Photons are particles with a spin – 1. Its spin direction is parallel to the direction of travel.