College Physics : Energy Quantization

Study concepts, example questions & explanations for College Physics

varsity tutors app store varsity tutors android store

Example Questions

Example Question #1 : Energy Quantization

A laser outputs light of a single color with photon energy . A nonlinear crystal, which halves the wavelength of light, is placed in the path of the laser beam. What is the energy of the photons exiting the crystal?

Possible Answers:

Correct answer:

Explanation:

Halving the wavelength is equivalent to doubling the frequency since for a light wave the wavelength and frequency are related by , where is the speed of light. The energy of a photon is , where is Planck's constant, so the photon energy is doubled.

Example Question #2 : Energy Quantization

A monochromatic light source is incident on a neutral density filter which decreases the light source's intensity by a factor of 3 but does not change its color. What happens to the energy of a photon in the less intense beam?

Possible Answers:

None of these

The photon energy decreases only slightly.

The photon energy increases by a factor of 3.

The photon energy decreases by a factor of 3.

The photon energy decreases by a factor of 9.

Correct answer:

None of these

Explanation:

The photon energy does not change since the color of light (and therefore the frequency of the light) does not change.

Learning Tools by Varsity Tutors

Incompatible Browser

Please upgrade or download one of the following browsers to use Instant Tutoring: