Why the water waves bend in diffraction?

[Aladin]

Waves bend when they pass throungh a narrow gap.It is the definition of diffraction.
what is the reason that when the water waves pass through a narrow gap in ripple tank the wavefronts become circular?
what is the reason that when the water waves pass through a wide slit in ripple tank the wavefronts remain straight?
please explain.

 

[ObsessiveMathsFreak]

This can be explained using "[URL Principle[/URL], where the wavefront at any point is considered to generate a circular wave at every point to advance itself. I didn't say that very well, but the Link may explain better. Be sure to check out the java applets link at the bottom of the Wikipedia page.

I like to think of it in this way. Whenever a wave encounters a "disturbance", it will generate a circular "ripple" centered at that disturbance. This sort of explains reflection, refraction and diffusion.

 

[astrokreng]

The phenomenon of water waves bending in diffraction is a result of the wave's interaction with the edges of an obstacle or opening. When a wave encounters a narrow gap, the edges of the gap act as secondary sources of waves, creating interference patterns that cause the wave to bend and spread out. This is known as diffraction and is a fundamental characteristic of all types of waves, including water waves.

When water waves pass through a narrow gap, the wavefronts become circular because the interference patterns created by the edges of the gap cause the wave to spread out in all directions. This leads to the circular shape of the wavefronts. The extent of the diffraction is dependent on the size of the gap and the wavelength of the wave. The smaller the gap and the longer the wavelength, the more pronounced the diffraction effect will be.

On the other hand, when water waves pass through a wide slit, the wavefronts remain straight because the gap is large enough for the wave to pass through without significant interference. This results in the wavefronts maintaining their original direction and shape. However, there may still be some minor diffraction effects due to the edges of the slit, but they are not as pronounced as in the case of a narrow gap.

In summary, the reason for water waves bending in diffraction is due to the interference patterns created by the edges of an obstacle or opening. The size of the gap and the wavelength of the wave determine the extent of the diffraction effect. This phenomenon is an important concept in wave theory and has practical applications in various fields such as optics, acoustics, and fluid dynamics.