Momentum of a photon is?
Correct answer: C. hf/c
- A. 0
- B. λ
- C. hf/c
- D. mv
Explanation
By using the de Broglie wavelength equation.We know that λ = h/p where λ is the de broglie wavelength, h is planck's constant and p is the momentum.Therefore p = h/λ. We know that c = fλ and therefore λ = c/fsubsituting this equation in p = h/λ gives: p = hf/c
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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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