Centripetal Force
Key Stage 5
Meaning
Centripetal force is the resultant force acting on an object moving in a circular path, directed towards the centre of the circle.
About Centripetal Force
- A centripetal force is required to keep an object in circular motion.
- Centripetal force can be provided by tension, gravity, friction, or other forces depending on the situation.
- The absence of centripetal force leads to the object moving in a straight line due to inertia.
- Centripetal force is not a specific force but rather the result of existing forces like tension or gravitational force.
- Centripetal force is critical in designing structures and systems involving rotational motion, such as centrifuges, carousels and roller coasters.
Formula
The centripetal force acting on an object is given by the formula:
- \(𝐹=\frac{𝑚𝑣^2}{𝑟}\)
Where:
𝑣 is the speed or the linear velocity of the object at a given point along the circular path
and
𝑟 is the radius of the circular path.
Examples
- The tension in a string provides the centripetal force for a spinning ball on a string.
- Gravity provides the centripetal force for planets orbiting the sun.