Rest mass of photon is:
Correct answer: B. Zero
- A. Infinite
- B. Zero
- C. Equal to proton
- D. None of the above
Explanation
Photons are massless particles. The rest mass of a photon is zero. Unlike particles with mass, such as electrons or protons, photons do not have rest mass. Because light always travels with some speed and is never at rest. So it has zero rest mass. Irrespective of the intensity, all the photons which have the same frequency, possess the same energy.
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About Photons and the Particle Model of Light
The particle model treats light as photons with energy E equals hf and momentum related to wavelength. Questions involve the photoelectric effect, work function, threshold frequency, stopping potential and photon energy, while distinguishing particle behaviour from the wave description of interference and diffraction.
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