Animations of Acoustic Waves

1.

WAVE BASICS

2.

WAVE INTERACTION

3.

STANDING WAVES

4.

HEARING SOUNDS

5.

FURTHER CONCEPTS

6.

UNIVERSITY OF SOUTHAMPTON

WAVE INTERACTION

Refraction, Snells Law

This animation has been created to illustrate the phenomenon of wave refraction. Refraction of a wave occurs when a wave passes from one medium to another in which it has a different speed.

If a wave crosses a boundary between two media 1 and 2 in which the wave speeds are v1 and v2 respectively, then the ratio v1/v2 obeys Snells law of refraction:

v1/v2 = sin θ1/sin θ2 = λ1/λ2

where θ1 and θ2 are the angles made by the waves and the normal to the boundary (the dashed line in the animation) in media 1 and 2 respectively. The symbols λ1 and λ1 correspond to the wavelength in the media 1 and 2 respectively.

This example shows that by moving from a medium with high wave speed to a medium with low wave speed, waves are refracted towards the normal. When going from a medium with low wave speed to a medium with high wave speed, it will be refracted away from the normal as you can see by imagining this animation running backwards.

 WAVE INTERACTION Reflection Diffraction