A vacuum pressure gauge in which a relatively large volume of a low-pressure gas is compressed to a small volume in a glass apparatus (see illustration). The volume is reduced to an extent that causes the pressure to rise sufficiently to support a column of fluid high enough to read. This simple device, which relies on Boyle's law, is suitable for measuring pressures in the range 103 to 10-3 pascal. It is named after H. McLeod (1841–1923).
McLeod gauge
- amplitude modulation
- Ampère's law
- Ampère's rule
- Ampère, André Marie
- analyser
- analytical geometry
- anastigmatic lens
- and circuit
- Anderson, Carl David
- anechoic
- anemometer
- aneroid barometer
- angle modulation
- angle of incidence
- angle of reflection
- angle of refraction
- angstrom
- Angström, Anders Jonas
- angular displacement, velocity, and acceleration
- angular frequency
- angular magnification
- angular momentum
- anharmonic oscillator
- anion
- anisotropic