Circular motion speed tool

Circular Velocity Calculator

Solve circular velocity, radius, or period using v = 2πr ÷ T.

Enter two known values

Solve a circular velocity problem

Free tool
m/s

This is the value being calculated.

m

Positive radius of the circular path.

s

Positive time required for one complete revolution.

Use meters per second for velocity, meters for radius, and seconds for the period.

Try an example:

Your circular velocity result will appear here

Choose the missing variable and enter the other two known values.

Physics overview

What is circular velocity?

Circular velocity is the tangential speed of an object moving around a circular path. It equals the distance traveled in one revolution divided by the time required.

Formula

Circular velocity formula

Circular Velocityv = 2πr ÷ T

  • v is circular velocity in meters per second.
  • r is radius in meters.
  • T is period in seconds.

Worked example

A 5 m radius circle has a 10 s period

  1. Write the formula: v = 2πr ÷ T.
  2. Substitute the values: v = 2 × π × 5 ÷ 10.
  3. Calculate the velocity: v ≈ 3.1416 m/s.

Rearranged equations

Solve for radius or period

Radius

r = vT ÷ 2π

Multiply velocity by period, then divide by 2π.

Period

T = 2πr ÷ v

Divide the circumference by circular velocity.

Distance traveled

Why the formula uses 2πr

The expression 2πr is the circumference of the circular path. An object traveling one complete revolution covers this distance during one period.

Units

Standard SI units

Use meters per second for circular velocity, meters for radius, and seconds for period.

Real-world applications

Where circular velocity is used

  • Rotating laboratory equipment.
  • Wheels, pulleys, and turntables.
  • Circular tracks and amusement rides.
  • Planetary and satellite motion.
  • Circular-motion experiments.

Calculation limits

Important assumptions

  • Velocity, radius, and period must be greater than zero.
  • Motion is assumed to follow a circular path.
  • Velocity represents tangential speed.
  • Period represents one complete revolution.
  • Units are not converted automatically.

Related tools

Use the Centripetal Force Calculator to calculate inward force, mass, velocity, or radius.

Use the Kinetic Energy Calculator to calculate energy from mass and velocity.

Questions and answers

Circular velocity calculator FAQ

What formula does the circular velocity calculator use?

It uses v = 2πr ÷ T, where circular velocity equals the circumference of the circular path divided by the period.

What is circular velocity?

Circular velocity is the tangential speed of an object moving around a circular path.

What is the period in circular motion?

The period is the time required for one complete revolution.

How do you calculate radius from circular velocity?

Multiply velocity by period and divide by 2π using r = vT ÷ 2π.

Accuracy and transparency

Created and maintained by our editorial team

This physics calculator is maintained by the Science Lab Tools Editorial Team. Its calculation logic is tested with representative inputs, while the supporting guidance is checked for formula clarity, units, assumptions, and common mistakes.

Learn more about our formula-review and correction process, or read about Science Lab Tools.

  • Calculation logic tested
  • Variables and units explained
  • Assumptions stated clearly
  • Corrections handled transparently