P12.27 Pulsed lasers are powerful sources of nearly mono- chromatic radiation. Lasers that emit photons in a pulse of 5.00 ns duration with a total energy in the pulse of 0.175 J at 875 nm are commercially available. a. What is the average power (energy per unit time) in units of watts (1 W = 1 J/s) associated with such a pulse? b. How many photons are emitted in such a pulse?

P12.27 Pulsed lasers are powerful sources of nearly mono- chromatic radiation. Lasers that emit photons in a pulse of 5.00 ns duration with a total energy in the pulse of 0.175 J at 875 nm are commercially available. a. What is the average power (energy per unit time) in units of watts (1 W = 1 J/s) associated with such a pulse? b. How many photons are emitted in such a pulse?

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter28: The Atom

Section: Chapter Questions

Problem 41A

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