Potentiometer, an electrical device that measures potential difference between two points in a circuit by comparison with a standard battery of known potential difference. The name is also applied to a variable resistor that provides varying amounts of potential difference.
Atoms: the building blocks of life and the universe. We're all made of these microscopic bits of matter, but how many does it take to make a complete human being? And exactly what kinds of atoms do we have inside us?
Nuclear materials get used in many forms of nuclear medicine -- everything from PET scans to chemotherapy uses them. Learn how nuclear medicine works.