circular motion

physics

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July 23, 2026

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Circular motion describes an object moving along a circular path. When an object moves in a circle, its velocity, a vector quantity, constantly changes direction, resulting in acceleration. This acceleration, known as centripetal acceleration, is directed towards the center of the circle. Its magnitude is calculated as the square of the object's speed divided by the radius of the circle ((a_c = v^2/r)).12

A force directed towards the center of rotation is required to maintain this curved path. This force is called centripetal force. Uniform circular motion specifically refers to movement at a constant speed along a circle.1324

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mechanics
Circular motion
Consider a particle moving along the perimeter of a circle at a uniform rate, such that it makes one complete revolution every hour. To describe the motion mathematically, a vector is constructed from the centre of the circle to the particle. The vector…
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Consider a particle moving along the perimeter of a circle at a uniform rate, such that it makes one complete revolution every hour. To describe the motion mathematically, a vector is constructed from the centre of the circle to the particle. The vector…
Read More

mechanics
History
…in the Platonic ideal of circular motion. Before Copernicus, astronomers had tried to account for the observed motions of heavenly bodies by imagining that they rotated on crystal spheres centred on Earth. This picture worked well enough for the stars but not for the planets. To “save the appearances” (fit…
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…in the Platonic ideal of circular motion. Before Copernicus, astronomers had tried to account for the observed motions of heavenly bodies by imagining that they rotated on crystal spheres centred on Earth. This picture worked well enough for the stars but not for the planets. To “save the appearances” (fit…
Read More