What is centripetal acceleration?

Centripetal acceleration is the inward acceleration experienced by an object moving along a circular path. It is always directed toward the center of the circle and is what keeps the object on its curved trajectory. The magnitude is given by a = v²/r or equivalently a = ω²r.

What is the difference between a = v²/r and a = ω²r?

Both formulas calculate the same centripetal acceleration but use different inputs. a = v²/r uses the linear (tangential) speed v and the radius r. a = ω²r uses the angular velocity ω (in rad/s) and the radius r. Since v = ωr, both forms are mathematically equivalent.

How do I convert RPM to rad/s?

Multiply the RPM value by 2π and divide by 60: ω (rad/s) = RPM × 2π / 60. For example, 300 RPM = 300 × 2π / 60 ≈ 31.42 rad/s. This calculator handles the conversion automatically when you select RPM as the unit.

Is centripetal acceleration the same as centrifugal acceleration?

No. Centripetal acceleration is a real inward acceleration in an inertial reference frame. Centrifugal acceleration is a fictitious outward effect perceived in a rotating (non-inertial) reference frame. They have the same magnitude but opposite directions.

What units does centripetal acceleration use?

The SI unit is meters per second squared (m/s²). Results can also be expressed in g (standard gravity, 1 g ≈ 9.80665 m/s²), ft/s², or cm/s². This calculator shows the result in all four units simultaneously.

Centripetal Acceleration Calculator

Name: Centripetal Acceleration Calculator
Availability: InStock
Author: Nham Vu

Compute centripetal acceleration from linear speed and radius, or angular velocity and radius, with instant unit conversions.

Centripetal Acceleration

Input Mode

Radius (r)

Linear Speed (v)

Enter values on the left and click Calculate.

Summary

Compute centripetal acceleration from linear speed and radius, or angular velocity and radius, with instant unit conversions.

How it works

Select the input mode: Linear Speed (v and r) or Angular Velocity (ω and r).
Enter the radius of the circular path and choose its unit (m, cm, km, ft, in).
Enter the speed or angular velocity and select the matching unit.
Click Calculate to see the centripetal acceleration with a full unit breakdown.
Switch modes at any time to cross-check your results.

Use cases

Determine the centripetal acceleration of a car rounding a curve at highway speed.
Calculate the acceleration experienced by passengers on a spinning fairground ride.
Find the centripetal acceleration of a satellite in low Earth orbit.
Verify the g-force on a rotating centrifuge rotor in a laboratory.
Solve circular motion problems in high-school and university physics.
Estimate the inward force needed to keep a drone in a banked turn.
Check the acceleration of a spinning wheel or gear given its RPM and radius.
Analyze the load on bearings for rotating machinery.

Frequently Asked Questions

Last updated: 2026-06-11 · Reviewed by Nham Vu