Light meeting obstacles
Physics Narrative for 5-11 11-14
What happens when light travels through the air and meets the surface of an object, such as a table, mirror, window, or curtain? Various outcomes are possible.
Notice that all of the energy of the incident beam can only be shared out amongst the three possibilities: energy is conserved.
If the object is:
- Opaque: no light is transmitted (the light is reflected and absorbed to varying degrees).
- Translucent: some light is transmitted (the rest of the light is reflected and absorbed to varying degrees).
- Transparent: ideally all light is transmitted (although in practice some light will be reflected and absorbed).
Notice that all the energy must be accounted for – energy is conserved.