Diffraction of Waves

[ No Votes ]

In addition to the revision notes for Diffraction of Waves on this page, you can also access the following Waves learning resources for Diffraction of Waves

Waves Learning Material
Tutorial IDTitleTutorialVideo
Tutorial
Revision
Notes
Revision
Questions
11.2Diffraction of Waves


In these revision notes for Diffraction of Waves, we cover the following key points:

  • What is diffraction?
  • What are the conditions for diffraction to occur?
  • What happens to the shape of waves in diffraction?
  • What is the relationship between diffraction and interference?
  • What does Huygens Principle say on diffraction of waves?

Diffraction of Waves Revision Notes

By definition, diffraction is the process by which a wave is spread out as a result of passing through a narrow aperture or across an edge, typically accompanied by interference between the waveforms produced.

The condition to obtain diffraction is that the dimensions of aperture or of the obstacle must be comparable to wavelength. When the aperture is much larger than the wavelength, no diffraction occurs and when the aperture is smaller than wavelength, circular wavefronts are produced. If the aperture enlarges, waves straighten because they experience diffraction only at the edges of aperture. The same phenomenon occurs when a wave encounters a small obstacle as well.

Diffraction of sound waves enables us to hear even when the speaker is round a corner of a building. This is because sound waves produced by the speaker bend around small obstacles such as the building walls.

Diffraction and interference are related concepts as interference is produced when diffraction from two or more openings does occur. Diffraction from two or more sources produce interference but interference cannot produce diffraction. Therefore, the relationship between diffraction and interference is unilateral.

The amount of diffraction (the sharpness of the bending) increases with increasing wavelength and decreases with decreasing wavelength for a constant opening. In fact, when the wavelength of the mechanical wave is smaller than the obstacle, no noticeable diffraction occurs.

The Dutch scientist Christiaan Huygens developed a useful technique for determining in detail how and where waves propagate during diffraction. Starting from some known position, Huygens's principle states that every point on a wave front is a source of wavelets that spread out in the forward direction at the same speed as the wave itself. The new wave front is tangent to all of the wavelets.

Whats next?

Enjoy the "Diffraction of Waves" revision notes? People who liked the "Diffraction of Waves" revision notes found the following resources useful:

  1. Revision Notes Feedback. Helps other - Leave a rating for this revision notes (see below)
  2. Waves Physics tutorial: Diffraction of Waves. Read the Diffraction of Waves physics tutorial and build your physics knowledge of Waves
  3. Waves Practice Questions: Diffraction of Waves. Test and improve your knowledge of Diffraction of Waves with example questins and answers
  4. Check your calculations for Waves questions with our excellent Waves calculators which contain full equations and calculations clearly displayed line by line. See the Waves Calculators by iCalculator™ below.
  5. Continuing learning waves - read our next physics tutorial: Types of Waves. The Simplified Equation of Waves

Help others Learning Physics just like you

[ No Votes ]

We hope you found this Physics tutorial "Diffraction of Waves" useful. If you did it would be great if you could spare the time to rate this physics tutorial (simply click on the number of stars that match your assessment of this physics learning aide) and/or share on social media, this helps us identify popular tutorials and calculators and expand our free learning resources to support our users around the world have free access to expand their knowledge of physics and other disciplines.

Waves Calculators by iCalculator™