🎡 Centripetal Force Calculator
Find the centripetal force needed for circular motion (F = mv²/r), or solve for mass, speed or radius.
Centripetal force F
40 N
Centripetal force F = m·v²/r; centripetal acceleration a = v²/r points toward the centre. 🔒 Computed in your browser.
How the centripetal force calculator works
An object moving in a circle needs a centre-directed (centripetal) force F = mv²/r, producing acceleration a = v²/r. Enter any three of force, mass, speed and radius and the tool solves for the fourth.
Centripetal force isn’t a new kind of force — it’s whatever provides the inward pull (tension, gravity, friction). There is no outward “centrifugal force” in an inertial frame.
Frequently asked questions
How do I calculate centripetal force?
F = mv²/r, where m is mass, v speed and r the radius. A 2 kg object at 10 m/s on a 5 m radius needs F = 2 × 100 / 5 = 40 N inward.
What is centripetal acceleration?
The centre-directed acceleration of circular motion: a = v²/r (= ω²r). It changes the direction of velocity, not its magnitude.
What provides the centripetal force?
Some real force directed toward the centre — string tension for a whirled ball, gravity for an orbit, friction for a car cornering. Centripetal is the role, not the type.
Is centrifugal force real?
In an inertial frame, no — the outward feeling is inertia resisting the inward acceleration. “Centrifugal force” only appears as a fictitious force in a rotating reference frame.
How does speed affect the force?
Force scales with v², so doubling the speed quadruples the centripetal force needed — which is why cornering fast requires so much more grip.