The rest mass of a photon is:
Correct answer: D. Zero
- A. hv/c²
- B. hv/c
- C. hv
- D. Zero
Explanation
Photons travel at the speed of light and have zero rest mass, as per special relativity.
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About Dawn of Modern Physics
Classical physics cannot explain blackbody radiation and related observations, leading to Planck’s quantum theory, in which energy is emitted or absorbed in discrete packets. Photons provide the particle model of light, with energy and momentum linked to frequency and wavelength, including the photoelectric effect and its threshold frequency.
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