What is the difference between cetrifugal force and centripetal force?

Answer 1

Centripetal force is the force that is applied to a moving object to cause it to travel in a circular path. The centripetal force constantly pulls the object toward the center of its path, so that it is constantly changing direction, rather than travelling in a straight line (i.e., centripetal force keeps it from "going off on a tangent").

Centrifugal force is a "phantom" force that resists the centripetal force. (It is the "equal and opposite force" that opposes centripetal force.)

For example, if you have an object on the end of a string and you swing it in a circle, you are supplying the centripetal force. But you can feel the object pulling away from you, pulling on the string as you swing it around. This is the so-called centrifugal force.

But what we call centrifugal force is simply the inertia of the object that you are swinging around (which is why I called it a "phantom" force). As you constantly change the direction that the object is travelling, you are exerting a force against a mass. According to Newton, F=ma. That is, the force you exert is equal to the mass you are swinging times the acceleration that you are giving it. (Note: In this case, "acceleration" doesn't mean that you're making it go faster, but that you are changing the DIRECTION of its velocity. Any change in the amount OR DIRECTION of the object's velocity is an example of acceleration.) So the "force" that you feel pulling against you (through the string) is actually mass times acceleration (i.e., it is a result of the object's mass and the acceleration that you are imparting to it).

If you were to push a stationary bowling ball with your hand, the ball would start to roll away (i.e., you would accelerate it). But as you push, you would feel the ball "resisting" the push you give it. That "resistance" is a result of the ball's inertia, and it is the "equal and opposite force" that we often hear about. This resisting force is exactly analogous to what we call "centrifugal force" in the case of the rotating object.

Answer 2

I agree with those who say centrifugal is a false force.

When you revolve, say on a caroussel, there is no force throwing you outwards, the force you feel is the want of trying to travel in a straight line (Newtons law) while the Caroussel is making you depart from that straight line.

Your hold on the Caroussel horse is the Centripetal force. If you stood up and leapt in the air, you would continue in a straight line, which might give the appearance of being thrown off the thing, but you will not be thrown perpendicular to your current motion, instead you will go off at a tangent to the circular path of the caroussel.

Either way, you will be thrown off. But this demostrates that there isn't a diametrically opposite force to the centripetal force, called centrifugal force.

Answer 3

Centripetal force is the force required to turn a body (prevent it from flying off into space). Centrifugal force is the illusion (felt by a person or object in the rotating body) of being pressed outward into the shell of the body (such as in a rotating centrifuge). It's an illusion, because actually what you feel is the centripetal force pushing you inward (making your path curve).

Answer 4

Centripetal force is the force that makes an object move in a circular path - gravity for an orbiting satellite, for example. Centrifugal force is the inertial reaction caused by circular motion. An example is the way you're forced to lean outward when your car takes a fast curve. Centrifugal force is often referred to as a pseudo-force. It doesn't show up in a force analysis in an inertial frame (that is, from a non-rotating point of view) .

Answer 5

Centripetal forces is an actual force - it is the force pulling an object towards the center of its orbit (gravity in the case of a planet). Without centripetal force, the orbiting object would fly off (at a tangent to the circle it is orbiting.)

centrifugal force is, in most cases, pseudo-force (a fake force) - it doesn't actually exist. It is the force that appears to be pulling the object away from the center of the orbit. in most cases, centrifugal force is fake because there is no force actually pulling away from the center of the orbit - it just feels that way to someone in the rotating frame of reference. the only time centrifugal force is real is when there is acceleration towards the center of the orbit.