Nepedia
Back to Discover
Fluent Reader
⚛️

Centripetal force

physical science Maturity 7-9 Next article →

Have you ever wondered what keeps a planet from flying off into deep space?

Centripetal force diagram
Centripetal force diagram

It all happens because of centripetal force. The name comes from Latin words meaning "center" and "to seek." This is a force that makes an object follow a curved path. Instead of moving in a straight line, the object is drawn toward a specific point. This point is the center of the curve the object is following. Without this force, objects would simply keep going straight.

Velocity-acceleration
Velocity-acceleration

This force works by pulling or pushing an object toward the middle of its path. For example, if you swing a ball on a rope, the tension in the rope pulls the ball inward. This is a "pull" force. In a carnival ride called a Rotor, a wall might push against you to keep you moving in a circle. This is a "push" force. In space, gravity acts as the centripetal force for many things. It provides the pull that keeps satellites and planets in their orbits.

Circular motion vectors
Circular motion vectors

Scientists have studied these curved paths for a long time. A Dutch physicist named Christiaan Huygens worked out the math for this in 1659. Later, Isaac Newton used the term to describe how bodies are drawn toward a center. He described it as a force that impels or draws things toward a point. Newton's work helped us understand how gravity creates astronomical orbits. His ideas helped explain how the universe stays organized.

Local unit vectors
Local unit vectors

There are important rules for how much force is needed to make a turn. The amount of force depends on the mass of the object and its speed. If an object moves along a circle, it experiences centripetal acceleration. This acceleration is calculated by taking the speed squared and dividing it by the radius. Because speed is squared, the force changes quickly. If you double the speed, you actually need four times the force to stay on the path.

Banked turn
Banked turn

You can see these rules in action in many different places. In particle accelerators, scientists move tiny particles at speeds close to the speed of light. At these extreme speeds, the math changes because of something called the Lorentz factor. This factor accounts for how the mass of the particle behaves at high speeds. You can also see this force when a charged particle moves through a magnetic field. In that case, the magnetic force acts as the centripetal force.

Stylised atom with three Bohr model orbits and stylised nucleus
Stylised atom with three Bohr model orbits and stylised nucleus
399 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (12)
File:Velocity-acceleration.svg
Velocity-acceleration.svg
File:Circular motion vectors.svg
Circular motion vectors.svg
File:Banked turn.svg
Banked turn.svg
File:Centripetal force diagram.svg
Centripetal force diagram.svg
File:Nonuniform circular motion.svg
Nonuniform circular motion.svg
File:Stylised atom with three Bohr model orbits and stylised nucleus.svg
Stylised atom with three Bohr model...
File:Acceleration vector plane polar coords.svg
Acceleration vector plane polar coords.svg
File:Force acting as centripetal force.svg
Force acting as centripetal force.svg
File:Velocity vector plane polar coords.svg
Velocity vector plane polar coords.svg
File:Position vector plane polar coords.svg
Position vector plane polar coords.svg
File:Local unit vectors.PNG
Local unit vectors.PNG
File:Polar unit vectors.PNG
Polar unit vectors.PNG
More to explore

🔗 What's this?

Concepts mentioned in this article

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.