This film demonstrates the measurement of the speed of light in both air and water using experimental setups. The first ...

Parabolic reflectors are pretty handy devices ... be optimized enough to produce astronomy-grade mirrors for visible light, but it still has a lot of potential applications.

A light rigid structure (of aluminum or other material ... making it particularly suitable for recording high frequency sounds such as birdsong. Schematic diagram of a parabolic reflector. Incoming ...