Using the model
Symbols, assumptions and limitations
The object moves on a circle of constant radius with constant speed magnitude. Velocity remains tangent to the path while centripetal acceleration and the net radial force point toward the centre. The force result requires the object’s mass.
Worked examples
See the method in practice
Known tangential speed
At 10 m/s on a 2 m radius, the angular speed is 5 rad/s and centripetal acceleration is 50 m/s².
Known period
A 3 m radius with a 2 s period gives a speed of about 9.425 m/s and a frequency of 0.5 Hz.
Questions
Frequently asked
Is centripetal force a new type of force?
No. It is the name for the net inward force, which may be supplied by tension, gravity, friction, a normal force, or their combination.
Why is there acceleration at constant speed?
Velocity includes direction. Its continuously changing direction produces an inward acceleration even when its magnitude stays constant.
Can I use rpm?
Yes. Revolutions per minute are converted internally to angular speed or frequency in SI units.
Sources & review
Equations and examples are checked against the references below. Results are educational and should be independently verified for safety-critical work.
OpenStax University Physics — Uniform Circular MotionWritten by the STEM Hub editorial team · Reviewed August 11, 2026 · Review methodology