The centripetal force calculator computes the inward force required to keep an object moving in a circle. Using F = mv²/r, it also calculates centripetal acceleration, angular velocity, and period of revolution. Supports both metric and imperial units.
Centripetal Force Calculator
Step-by-Step
Formula Reference
How to Use the Centripetal Force Calculator
Centripetal force is the net inward force keeping an object in circular motion. Without it, the object would fly off in a straight line (Newton's first law). This calculator finds force, acceleration, angular velocity, and period from mass, speed, and radius.
Step 1: Select Unit System
Toggle between Metric (kg, m/s, m, N) and Imperial (lb, ft/s, ft, lbf). The calculator converts internally and displays results in your chosen units.
Step 2: Enter Mass, Speed, and Radius
Enter the mass of the moving object, its linear speed, and the radius of circular motion. All three values are required.
Example: Car on a Curve
A 1500 kg car travels at 20 m/s (72 km/h) around a curve with r = 100 m. F = 1500 × 20² / 100 = 1500 × 400 / 100 = 6000 N. The acceleration is 4 m/s² inward. The angular velocity is 0.2 rad/s and the period is about 31.4 seconds.
What Provides the Centripetal Force?
For a car turning: friction between tires and road. For a satellite orbiting Earth: gravity. For a ball on a string: tension. For a charged particle in a magnetic field: the Lorentz force. The centripetal force is not a separate force — it is the net sum of existing forces directed toward the center.
Frequently Asked Questions
What is centripetal force?
Centripetal force is the net inward force required to keep an object moving in a circular path. It acts toward the center of the circle. The formula is F = mv²/r, where m is mass, v is speed, and r is the radius of the circular path.
What is the difference between centripetal and centrifugal force?
Centripetal force is a real inward force (like tension or friction) that causes circular motion. Centrifugal force is a fictitious outward force felt in a rotating reference frame — it doesn't actually exist in an inertial frame but feels real when you're the one rotating.
How do I calculate angular velocity?
Angular velocity ω = v/r, where v is the linear speed and r is the radius. It can also be expressed as ω = 2π/T where T is the period. Units are radians per second (rad/s).
Is this calculator free?
Yes, completely free with no signup required. All calculations run in your browser.
What are real examples of centripetal force?
Cars turning on a road (friction provides centripetal force), satellites orbiting Earth (gravity provides centripetal force), a ball on a string (tension provides centripetal force), and a centrifuge spinning samples in a lab.