Problem 24.06. A laser emits monochromatic light (light of a single frequency). A 5 mW (milliWatt) laser is enough to cause eye damage with an exposure of 1/100 of a second. (a) If the power of a laser is the energy per unit time, P = E/t, how much energy is emitted by a 5 mW laser in 1/100 seconds? (b) If the light of this laser is red with a wavelength of 700 nm, how many photons are emmitted in this flash of light to transmit the energy calculated in part a? (Hint: The total energy is the energy of a single photon of that wavelength times the number of photons).

Problem 24.06. A laser emits monochromatic light (light of a single frequency). A 5 mW (milliWatt) laser is enough to cause eye damage with an exposure of 1/100 of a second. (a) If the power of a laser is the energy per unit time, P = E/t, how much energy is emitted by a 5 mW laser in 1/100 seconds? (b) If the light of this laser is red with a wavelength of 700 nm, how many photons are emmitted in this flash of light to transmit the energy calculated in part a? (Hint: The total energy is the energy of a single photon of that wavelength times the number of photons).

Inquiry into Physics

8th Edition

ISBN:9781337515863

Author:Ostdiek

Publisher:Ostdiek

Chapter8: Electromagnetism And Em Waves

Section: Chapter Questions

Problem 33Q

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