Interface
Key Stage 4
Meaning
An interface is the place where two different materials or media meet.
About Interfaces
- The interface between two media can have an effect on waves travelling through it.
- Waves can be transmitted (and refracted), reflected or absorbed at the interface between two media.
- The effect of an interface on a wave depends upon the relative properties of two media including density and refractive index.
- When a wave is transmitted from one medium into another it changes speed and wavelength but it's frequency remains constant. The change in wave speed causes refraction in which the wave changes direction. The degree of refraction of the wave depends upon the angle of incidence that the wave strikes the interface.
- When a wave is reflected form a surface this is because the difference between density or refractive index of the two media is large. The wave bounces off the interface following the law of reflection.
- When a wave is absorbed the energy is transferred into the thermal energy store of a material.