The rest mass of photon is
Correct answer: A. Zero
- A. Zero
- B. 0.5 gram
- C. 1 gram
- D. 10 gram
Explanation
The rest mass of a photon is zero. Photons are unique because they are elementary particles that travel at the speed of light, as described by the theory of relativity. Only particles with zero rest mass can achieve light speed in a vacuum. Thus, Option A is correct, reflecting this essential property of photons. Options B, C, and D incorrectly suggest that photons have a non-zero rest mass, which violates the established principles of modern physics.
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About Optics
Light is studied through reflection, refraction, dispersion, interference, diffraction and polarization, linking ray behavior with its wave nature. Questions may involve mirrors, lenses, optical instruments, refractive index and image formation, while geometrical optics deals with rays and wave optics explains effects such as interference and diffraction.
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