In classical mechanics, a central force on an object is a force whose magnitude only depends on the distance r of the object from the origin and is directed along the line joining them:
where is the force, F is a vector valued force function, F is a scalar valued force function, r is the position vector, ||r|| is its length, and = r/||r|| is the corresponding unit vector.
Equivalently, a force field is central if and only if it is spherically symmetric.
Read more about Central Force: Properties, Examples
Famous quotes containing the words central force, central and/or force:
“For us necessity is not as of old an image without us, with whom we can do warfare; it is a magic web woven through and through us, like that magnetic system of which modern science speaks, penetrating us with a network subtler than our subtlest nerves, yet bearing in it the central forces of the world.”
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“If an ox will not drink water, you cannot force its head down to drink.”
—Chinese proverb.