What is a variable speed drive? A variable speed drive is a piece of equipment that regulates the speed and rotational force, or torque output, of an electric motor. The background and technology. There are millions of motors in use in industry and offices around the world.
The specific gravity for Obsidian is 2.35, it's refractive index is 1.48-1.51, and it's double refraction is None. History Obsidian is named after a Roman, Obsius.
Specific Gravity. Specific Gravity, or relative density of materials, is an important property used in many calculations for mix design, proportioning, bulk density, absorption and void content of aggregates and other construction materials. Gilsonâs exclusive Specific Gravity equipment yields accurate, repeatable results and meets ASTM C127/128 specifications.