radius vector

American  

noun

plural

radii vectores, radius vectors

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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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

And the way it increases will be for the radius vector to lengthen, so as to sweep out a bigger area.

From Pioneers of Science by Lodge, Oliver, Sir

The area covered would always be uniform, because the radius vector would always be uniform in length.

From Aether and Gravitation by Hooper, William George

In Kepler's form of stating the law the radius vector is supposed to travel with the planet and in each day to sweep over the same fractional part of the total area of the orbit.

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

The speed of the latter may, therefore, be expressed as a function of its radius vector at the moment and of the major axis of its orbit without introducing any other elements into the expression.

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