What Is Centripetal Force?

Centripetal force is the net inward force required to keep an object moving along a curved path. For circular motion at speed v on a circle of radius r, Fc = mv2/r = mω2r, directed toward the centre.

Centripetal force is not a new kind of force — it is the role played by an existing force such as tension (ball on a string), gravity (planet in orbit), normal force (banked curve), or static friction (car cornering). On a free-body diagram the inward arrow is one of these labelled forces, not a separately drawn "centripetal force."

Common mistake: writing "centrifugal force" on an inertial-frame diagram. In the rotating frame attached to the moving object, the outward-pointing centrifugal pseudo-force mω2r balances the centripetal force; in the lab frame there is no outward force.

Recent research on this topic from arXiv

Preprints and papers indexed on arXiv.org. Links open the public abstract pages.

Where to go next