Java Physics



Diffraction of Wave (Opening)



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Same applet, larger size

Diffraction by an obstacle (Applet)

Bending of waves around a corner (Applet)

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narrow slit

When waves reach a narrow slit, the water in the slit vibrates like a point source. The waves thus sent out from secondary sources along the slit are nearly in-phase when arriving any point in the forward direction. The diffracted wave resembles a circular wave with centre at the slit.

wide slit

A wave spreads out (noticeable diffraction) when the size of the slit is comparable to or smaller than the wavelength.



  • The author (Chiu-king Ng) has the copyright on all the simulations in this website.
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  • Last Update:2017-6-5