A laser emits light of wavelength 463 nm during a brief pulse that lasts for 25 ms and has a total energy of 1.2 J. How many photons are emitted in that single pulse? (c = 3.00 × 10⁸m/s, h = 6.626 × 10^-34 J ∙ s) A) 2.8 × 10¹⁸ B) 6.9 × 10¹⁹ C) 3.4 × 10¹⁹ D) 1.1 × 10¹⁷ E) 2.2 × 10¹⁷

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Quizplus · Accepted Answer

The energy of a single photon is given by E = hc/λ, where h is Planck's constant, c is the speed of light, and λ is the wavelength. The total energy of the pulse is 1.2 J, so the number of photons emitted is:N = E/(hc/λ) = (1.2 J)/(6.626 × 10^-34 J ∙ s * 3.00 × 10^8 m/s * 463 × 10^-9 m) = 2.8 × 10^18 photons

A Laser Emits Light of Wavelength 463 Nm During a Brief