Why is the centripetal force necessary for circular motion?

The centripetal force can be thought of as the force that causes circular motion.

When an object moves in a circle a force must always act on it, even when it moves at a constant speed. This is because velocity is a vector (and therefore has both a magnitude and a direction) and the direction the object is moving in is constantly changing.

This constant direction change is an acceleration, and we know from Newton's Second Law that any acceleration must have an force associated with it.

Similarly, the centripetal force must point towards the centre of the circle, and therefore perpendicular to the tangential velocity, to maintain the motion in the circle. If it did not exist the object would 'shoot off' in a direction tangential to the circle.

JB
Answered by James B. Physics tutor

24120 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

A ball of mass m is thrown from the ground at the speed u=10ms^-1 at an angle of 30 degrees. Find the max height, the total flight time and the max distance it travels?Assume g=10ms^-1 and there is no air friction


Show Maxwell's equations in free space satisfy the wave equation


I have trouble visualizing simple harmonic motion, and remembering all the related equations. How should I think about it?


Explain what is meant by the term "plastic deformation".


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning