What is the energy of a photon in a beam of infrared radiation of wavelength 1240nm?
Correct answer: A. 1.0 eV
- A. 1.0 eV
- B. 3.0 eV
- C. 5.0 eV
- D. 7.0 eV
Explanation
Photon velocity equals the speed of light. Photons are massless, but they have energy E = hf = hc/λ. Here h = 6.626*10-34 Js is called Planck's constant. The photon energy is inversely proportional to the wavelength of the electromagnetic wave.E=6.626×10−34 × 3×108 /1240×10-9 ≈ 1.00 eV.
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