Centrifugal Force in Simple Terms?

Question

What exactly is centrifugal force?

Is there an equation for this type of force?

Where do we find centrifugal force on Earth and where do we find it in space?

Answer 1

kagerendan is mistaken--"centripetal" force and "centrifugal" force are definitely two different things. In fact, they have opposite meanings: "Centripetal" means "center-seeking", while "centrifugal" means "center-fleeing."

But in fact, they are related. Centrifugal force describes the feeling of being flung to the outside of a curved path. For example, when you make a sharp left turn, you feel like you're being pulled to the right (to the outside of the curve).

It's sometimes called a "fictitious force," because it really results from being pushed toward the CENTER of the curve. The way a physicist would explain the "left turn" experience, would be as follows: He'd say that the car is pushing your body to the LEFT (toward the inside of the curve)--which is pretty obvious, otherwise your body would not be curving along with the car. By Newton's 3rd Law (action/reaction), when the car pushes left on you, you push RIGHT on the car.

So from a physicist's point of view, the only "real" force acting on you is a CENTRIPETAL force of the car pushing you TOWARD the center of the circle. But to you, it feel's like you're being pushed AWAY from the center of the circle; that's centrifugal force.

Generally, if you are thinking from a point of view outside of the rotating/curving object, it's easier to treat the problem in terms of centripetal force; while if you're thinking from a point of view within the rotating/curving object, it's often easier to analyze it in terms of "centrifugal" force.

There is an equation for this type of force. You need to know the radius of the circle; and you need to know either the velocity "v" of the moving object; or the rate ω (omega) at which it's spinning. (ω is measured in "radians per second"; divide it by 2π to get "revolutions per second".)

centripetal/centrifugal acceleration:
In terms of "v" is: v²/r
In terms of ω is: ω²r

It's often more useful to calculate it as "acceleration" instead of "force," because then you can compare it directly to the "feel" of gravity. For example, if you want to build a space station that rotates at a speed that exactly simulates 1 earth gravity, then you need to make this equation true:

v²/r = g

where "g" is 1 earth gravity, or 9.8 m/sec²

We find centrifugal force on earth and in space wherever something moves in a curved path.

Answer 2

It's actually called centripetal force. I don't know when "centrifugal" started catching on, but it's probably because someone heard it wrong. They do sound similar. Now, centripetal force is simply the force that is applied to an object that keeps it moving in circles. For instance, if I hold a soda can on a spring and start spinning it around, then in order to keep it spinning I apply centripetal force to it by pulling it toward the center of the circle of motion. At the point when it is on top, I would be pulling down. When it is at the far left, I pull right, and so on. If I let go, the ball's current velocity will go unhindered by the centripetal force, and go flying in that direction. You can try it yourself and pay attention to how you're pulling it and see what I mean. In space, gravity works like a centripetal force to keep moons in orbit of planets. If the planet disappears, the moon will go in whatever direction it was currently going, instead of being pulled back by gravity. On earth there is the string example, and also at NASA there is the centrifuge (possible reason people say centrifugal) which moves the astronauts around to simulate a shuttle launch.

Answer 3

An example on Earth is a motor bike leaning over in a corner and not falling over.