radius vector

American  

noun

radii vectores, plural radius vectors plural

1. Mathematics. the length of the line segment joining a fixed point or origin to a given point.

2. Astronomy.

   1. the straight line joining two bodies in relative orbital motion, as the line from the sun to a planet at any point in its orbit.

   2. the distance between two such bodies at any point in the orbit.

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radius vector British  

noun

1. maths a line joining a point in space to the origin of polar or spherical coordinates

2. astronomy an imaginary line joining a satellite to the planet or star around which it is orbiting

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radius vector Scientific  

1. A line segment that joins the origin and a variable point in a system of polar or spherical coordinates.

2. The imaginary straight line that connects the center of the Sun or another body with the center of a planet, comet, or other body that orbits it.

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Other Word Forms

Inflected Forms

noun

• radius vectors
  plural
• radii vectores
  plural

Etymology

Origin of radius vector

First recorded in 1745–55

Example Sentences

Note that the torque vector is orthogonal to both the force vector and the radius vector.

From Textbooks • Mar. 30, 2016

Hodograph, hod′o-graf, n. a curve the radius vector of which represents in direction and magnitude the velocity of a moving particle—a term suggested by Sir W. R. Hamilton.

From Chambers's Twentieth Century Dictionary (part 2 of 4: E-M) by Various

M. Le Verrier then remarks, as one of the strong proofs of the correctness of the general theory, that the error of radius vector is explained as accurately as the error of longitude.

From Astronomical Discovery by Turner, Herbert Hall

Airy wrote expressing his interest, and asked for particulars about the radius vector.

From History of Astronomy by Forbes, George

So Kepler formulated his second great law of planetary motion very simply: the radius vector of any planet describes, or sweeps over, equal areas in equal times.

From Astronomy: The Science of the Heavenly Bodies by Todd, David Peck