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Question
List out the characteristics of photons.
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Solution
Characteristics of photons: According to the particle nature of light, photons are the basic constituents of any radiation and possess the following characteristic properties:
- The photons of light of frequency v and wavelength λ will have energy, given by
E = hv = `"hc"/λ` - The energy of a photon is determined by the frequency of the radiation and not by its intensity and the intensity has no relation with the energy of the individual photons in the beam.
- The photons travel with the velocity of light and its momentum is given by
p = `"h"/λ = "hv"/"c"` - Since photons are electrically neutral, they are unaffected by electric and magnetic fields.
- When a photon interacts with matter (photon-electron collision), the total energy, total linear momentum, and angular momentum are conserved. Since photons may be absorbed or a new photon may be produced in such interactions, the number of photons may not be conserved.
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