PHYS 2212 Module 13.1

The Propagation of Light

Recommended Reading

13.1 The Propagation of Light

Learning Objectives

By the end of this section, you will be able to:

  • Determine the index of refraction, given the speed of light in a medium
  • List the ways in which light travels from a source to another location

The Propagation of Light


Practice 13.1.1
When light passes from vacuum (index of refraction n = 1) into water (n = 1.333)…
Check your answer: B. the wavelength decreases and the frequency is unchanged.
Practice 13.1.2
A source emits monochromatic light of wavelength 495 nm in air. When the light passes through a liquid, its wavelength reduces to 434 nm. What is the liquid’s index of refraction?
Check your answer: C. 1.14
Practice 13.1.3
The speed of light in any material is slower for shorter wavelengths, so the index of refraction is greater for light of shorter wavelengths. For example, for a type of glass called crown glass, n = 1.50 for red light, and n = 1.53 for violet light, which has a shorter wavelength than red light.     Lenses in a camera use refraction to form an image on a film. Ideally, you want all the colors in the light from the object being photographed to be refracted by the same amount.

Of the materials shown in the figure, which should you choose for a camera lens?
Check your answer: C. Fused quartz