Number of photons emitted each second by a 100 W light bulb?

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Photons released by nuclear decays tend to be in the MeV range, and atomic nuclei are a few femtometers (10-15 m) across. If a single proton trapped in an inescapable rectangular box releases a 1.3 MeV photon when dropping from the n = 2 to the n = 1 state, how wide is the box, in femtometers? You should find that this quick and dirty estimate is remarkably close to the real size of a nucleus! The proton mass is about 1.7 x 10-27 kg. 1 MeV = 1.6 x 10-13 J. Planck's constant is approximately h = 6.6 x 10-34 J s.

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Chapter 10, Problem 4C

To determine

Number of photons emitted each second by a 100 W light bulb?

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Photons released by nuclear decays tend to be in the MeV range, and atomic nuclei are a few femtometers (10-15 m) across. If a single proton trapped in an inescapable rectangular box releases a 1.3 MeV photon when dropping from the n = 2 to the n = 1 state, how wide is the box, in femtometers? You should find that this quick and dirty estimate is remarkably close to the real size of a nucleus! The proton mass is about 1.7 x 10-27 kg. 1 MeV = 1.6 x 10-13 J. Planck's constant is approximately h = 6.6 x 10-34 J s.

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