In undisturbed elliptic motion, the constant angular speed required for a body of a specified mass to complete one revolution in an orbit of a specified semimajor axis.
Related Terms 
POLARIZING PYROMETER
A type of pyrometer, such as the Wanner optical pyrometer, in which monochromatic light from the source under investigation and light from a lamp with filament maintained at a constant but unknown temperature are both polarized and their intensities compared.

PLANE STRESS
A state of stress in which two of the principal stresses are always parallel to a given plane and are constant in the normal direction.

PHOTOELECTRIC CONSTANT
The ratio of the frequency of radiation causing emission of photoelectrons to the voltage corresponding to the energy absorbed by a photoelectron; equal to Planck's constant divided by the electron charge.

PERMITTIVITY
The dielectric constant multiplied by the permittivity of empty space, where the permittivity of empty space (0) is a constant appearing in Coulomb's law, having the value of 1 in centimetergramsecond electrostatic units, and of 8.854 10 12 farad/meter in rationalized meterkilogramsecond units.

NEWTON'S FIRST LAW
The law that a particle not subjected to external forces remains at rest or moves with constant speed in a straight line. Also known as first law of motion; Galileo's law of inertia.

NEWTONIAN REFERENCE FRAME
One of a set of reference frames with constant relative velocity and within which Newton's laws hold; the frames have a common time, and coordinates are related by the Galilean transformation rule.

METERING SCREW
An extrusiontype screw feeder or conveyor section used to feed pulverized or doughy material at a constant rate.

MAXIMUM WORKING AREA
[INDENG] That portion of the working area that is readily accessible to the hands of a worker when in his normal states that the difference between the specific heat of a gas at constant pressure and its specific heat at constant volume is equal to the gas constant divided by the molecular weight of the gas.

MAGNETIC FLUX QUANTUM
A fundamental unit of magnetic flux, the total magnetic flux in a fluxoid in a type II superconductor, equal to h/(2e), where h is Planck's constant and e is the magnitude of the electron charge, or approxiiron, nickel, or titanium, or nonmagnetic deposits which either contain magnetic gangue minerals or are associated with magnetic structures.

LOSSINWEIGHT FEEDER
A device to apportion the output of granulated or powdered solids at a constant rate from a feed hopper; weightmeasured decrease in hopper content actuates further opening of the discharge chute to compensate for flow loss as the hopper overburden decreases; used in the chemical, fertilizer, and plastics industries.
