| 释义 |
phase angle
[f. phase + angle n.2]
1. An angle representing a difference in phase, 360 degrees (2π radians) corresponding to one complete cycle.
1889J. A. Fleming Alternate Current Transformer I. iii. 110, OP..is called the amplitude or maximum value, and POM the phase angle of the motion. 1936Discovery Mar. 80/2 By phase-angle changes so produced..any of our mean amplitudes may be much reduced and the real importance of a periodicity [in the weather] accordingly masked proportionately. 1947R. Lee Electronic Transformers & Circuits v. 127 These waves indicate that the phase angle encountered in audio transformers does not of itself introduce much distortion in a lightly loaded triode. 1966Brosan & Hayden Adv. Electr. Power & Machines vii. 279 The voltage will be alternating, and..in general, e= Em sin ωt. If the coil is connected to an external circuit, a current will flow, given by i= Im sin (ωt- ψ) where ψ is the internal phase angle.
2. Astr. The angle between the lines joining a given planet to the sun and to the earth.
1926H. N. Russell et al. Astron. I. ix. 234 How much of the illuminated hemisphere can be seen from the earth depends upon the angle at the planet between lines to the earth and to the sun. Where this phase angle is always very small, as it is from the most distant planets, there is never any perceptible deviation from a circular disk. 1974R. H. Stoy Everyman's Astron. vi. 203 The apparent brightness of any minor planet varies inversely both as the square of its distance from the Earth and as the square of its distance from the Sun. It also depends on the phase angle, that is on the angle between the lines joining the minor planet to the Sun and to the Earth. |