Radiometer, an instrument designed to detect and measure radiant energy. A simple type, devised by Sir William Crookes, consists of four vanes of mica or aluminum foil that revolve on a needle point within a glass globe from which most of the air has been removed.
Expansion, an increase in the volume of a substance, usually due to the addition of heat to the substance. See more »
Heat, the energy possessed by molecules because of their motion. Since all solids, liquids, and gases are made of molecules that move about, all such substances contain heat. See more »
Frequency has to do with wave speed and wavelength is a measurement of a wave's span. Learn how frequency and wavelength of light are related in this article. See more »
Solid-state Physics, the branch of physics that deals with the structure and properties of solids. See more »
X Rays, electromagnetic radiation similar to that of visible light, but of much shorter wavelength. See more »
Calorie, a unit for measuring the amount of heat released or absorbed by a substance. See more »
Calorimeter, an instrument for measuring the amount of heat released or absorbed in physical and chemical processes. See more »
Capillary Action, or Capillarity, the tendency of liquids to rise or to be depressed in tubes of small diameter. See more »
Carat, a unit of weight for precious stones. The international, or metric, carat was standardized in 1913 and accepted by the United States and many other countries. See more »
Centrifuge, a machine that separates liquids of different densities. It can also separate liquids from solids that are held in suspension. See more »
