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

It is always subject to the law of inverse squares, and what is more, its repelling power coincides exactly with the path which the centripetal force takes, that is, the radius vector.

From Aether and Gravitation by Hooper, William George

The radius vector of each planet moves over equal areas in equal times.

From A Text-Book of Astronomy by Comstock, George C.

This force is in a direction perpendicular to the radius vector and to the plane containing it and the element of current.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 2 "Ehud" to "Electroscope" by Various

The problem of constructing successive radii vectores, the angles of which are measured off from the radius vector of the body at the original given position, is then a geometric one, known as Kepler’s problem.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 7 "Arundel, Thomas" to "Athens" by Various