Do you agree, that there is no such thing as centrifugal force? May I convince you?

Question

Centrifugal (away from center) force is the force that pulls something outwards when it travels along a radius, but what is pushing it out... Nothing. Inertia wants to keep that something traveling in a straight line but there must be another force keeping it in that radius. The centripetal (towards center) force is that force. So in short, when you go around a corner in a car, you don't push on the door, the door pushes on you. Do you agree?

I believe centrifugal force is a myth, there is only inertia and centripetal forces.

Answer 1

You're right. No need to convince me.

It's not a real force, but an apparent force. For circular motion, one needs a force to pull the particle/object towards the center. Inertia wants the object to keep going straight. So there is an apparent force on the object to resist the inward force. What it really comes down to is that Angular Momentum is conserved, therefore the object experiences a resistance to being pulled in.

Mathematically, the "centrifugal force" term comes from the "ma" side of F=ma (from Young and Freedman, University Phyiscs). So it's not a Force. Since it has the units of force, it is often taught to freshman physics students as a force (but good text books don't). This is an example of how just because something has the same units as something else doesn't mean they're the same thing. I guess a good term would be "pseudo-force."

Now I have to address something another responder said:
The center of gravity is just an "imaginary point" but a point of physical significance. It's the center of mass. Now if you were in the center of a hollow Earth, it's false to say that you would be pulled outward in every direction. In actuality, one can Mathematically show that gravity would be completely canceled out in a hollow spherical Earth. You wouldn't feel any gravitational atttraction at all. You don't even have to be at the center, but could go to the very edge. There would be no gravity. This is due to Gauss's Law. Weird, I know, but very true.

Answer 2

You are absolutely right. Even in a rotating coordinate system, the centrifugal effect or "pseudoforce" is not a real force and neither is the coreolis effect, hence the quantifier "effect".

When you go around the corner, linear momentum is what makes you tend to go forward, and centripetal accelleration is what pulls the door into you.

Some of these other folks are mistaken when they claim that you pushing out against the door is "centrifugal force". It is not. You pushing against the door is Normal Force.

I am often amused by folks who are dead wrong and don't know it.

Answer 3

I agree, that there is no such thing as centrifugal force.
When an object moves in a circle, it need a force toward the center of the circle. It is called centripetal force. It is only a name. The force can be friction, attraction by gravitation or electric.
There is no balance, because there is only one force, perpendicular to the speed.

Th

Answer 4

I agree in the sense you said, but --

The center of gravity is an an imaginary point, not the point from where all gravity originates.

If the earth were hollow, and you were inside, gravity would try to pull you away from the center. Therefore, centipetal force is a just as much a misnomer as centrifugal force.

Answer 5

Yes, inertia, governed by Newton's laws of motion, states that an object in motion will continue in motion, at the same velocity and direction, unless acted on by a force. In the constant-velocity car on a straight road, there is no such force, and you keep moving straight. If the car starts turning, you tend to keep going straight. The car seat or door exerts a force on you in the direction the car is turning and begins to accelerate you in that direction. That force is used to accelerate your mass (F = MA), not to overcome some other force like gravity. It's simply misleading to invent a 'force' in the outward direction. If there were such a force, it would balance or neutralize the force applied to you by the door,
and by Netwon's laws, you'd just keep going straight.

Answer 6

I agree.
The only force required for circular motion is the centre-seeking or centripetal force which prevents an object from following a path tangential to the circular path.
Centrifugal force is a mistaken attempt to explain the centrifuge effect.

Answer 7

Technically this is true. Centrifugal force is just a useful way of describing the way rotating objects act, not an actual physical force.

Answer 8

I kinda agree with you. Centrifugal force is just theoretical so it doesn't exist in natural but theories about it exist so I wouldn't go so far as to say there is no such thing. Centripetal force is the one that exists in every day life.

Answer 9

If you're up with the theory that 'gravity' itself is not a 'force' but merely a warping of time-space, then you'll agree that there is indeed a 'pulling force' on the outside of the radius - as well as the inside. Time-space would get warped during the travel along a curve, just as planets in their orbits warp it.

Answer 10

You're playing word games with physics. OF COURSE the door pushes you towrds the center. Call that force whatever you like.

WE call the the equal and opposite force (which ALWAYS exsits in the presence of the inward force):

CENTRIFUGAL FORCE

And we aren't likely to change just because you can't grasp the concept!