Moderate

Which light photon has the least momentum?

Correct answer: A. Red

  • A. Red
  • B. Green
  • C. Yellow
  • D. Blue

Explanation

The light photon with the least momentum is red. This is because red light has the longest wavelength of all visible light. The momentum of a photon is inversely proportional to its wavelength, so the photon with the longest wavelength will have the least momentum.The momentum of a photon can be calculated using the following equation:p = h/λwhere p is the momentum, h is Planck's constant, and λ is the wavelength.The wavelength of red light is about 700 nanometers, while the wavelength of blue light is about 400 nanometers. This means that the momentum of a red photon is about half the momentum of a blue photon.Therefore, the light photon with the least momentum is red.

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About Atomic Spectra

Atoms emit or absorb light at specific wavelengths because electrons occupy quantized energy levels and change levels by absorbing or releasing photons. The topic covers emission and absorption spectra, spectral series, hydrogen’s line spectrum, energy-level transitions, and the relation between wavelength, frequency and photon energy.

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