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power, in physics

(Encyclopedia)power, in physics, time rate of doing work or of producing or expending energy. The unit of power based on the English units of measurement is the horsepower, devised for describing mechanical power b...

precipitation, in chemistry

(Encyclopedia)precipitation, in chemistry, a process in which a solid is separated from a suspension, sol, or solution. In a suspension such as sand in water the solid spontaneously precipitates (settles out) on st...

precipitation, in meteorology

(Encyclopedia)precipitation, in meteorology, condensed moisture that falls to the surface of the earth in the form of rain, sleet, snow, hail, frost, or dew. ...

phase, in astronomy

(Encyclopedia)CE5 Phases of the moon phase, in astronomy, the measure of how much of the illuminated surface of a planet or satellite can be seen from a point at a distance from that body; the term is most ofte...

phase, in physics

(Encyclopedia)phase, in physics: see wave.

Phoebe, in astronomy

(Encyclopedia)Phoebe fēˈbē [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn IX (or S9), Phoebe is 137 mi (220 km) in diameter, orbits Saturn at a mean distance ...

phoebe, in zoology

(Encyclopedia)phoebe, in zoology: see flycatcher. ...

Pollux, in astronomy

(Encyclopedia)Pollux, brightest star in the constellation Gemini; Bayer designation Beta Geminorum; 1992 position R.A. 7h44.8m, Dec. +28°03′. An orange giant of spectral class K0 III, it is the nearest giant sta...

poplar, in botany

(Encyclopedia)poplar: see willow.

porcupine, in zoology

(Encyclopedia)porcupine, member of either of two rodent families, characterized by having some of its hairs modified as bristles, spines, or quills. The quills are loosely attached to the porcupines' skin and pull ...