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Loren Booda
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Is the "centrifugal force" fictitious or just incidental?
Is the "centrifugal force" fictitious or just incidental?
Is the "centrifugal force" fictitious or just incidental?
When pressed against the door on a curve you are experiencing a similar pair of forces as the door pushes inward on you through the curve. From the general reference frame outside the car it is clear that there is a pair of equal and opposite forces acting between the passenger and the car. From the specific reference frame inside the car, centrifugal force exists as a fictitious force which appears to try to eject you from the car as the door pushes on you to counteract your inertial tendency to keep moving in a straight line at a constant speed. When our state of motion changes our senses confuse the relationship between forces and inertia. As a result we feel forces acting on us in the opposite direction from the actual forces that are causing us to accelerate. This is because our perception of forces and motion evolved in a nonaccelerating reference frame and because there are always at least two objects involved which exert equal and opposite forces on each other.
Originally posted by NateTG
The cetrifugal force is part of accounting for an accelerated frame of reference. It corresponds to being in a reference frame that is accelerated.
I'm not sure what you mean by fictitious or incidental.e
Don't think of it as "fictitious" since its just as 'real' as any other force. Refering to it as an "inertial force" is much better.Originally posted by Loren Booda
Is the "centrifugal force" fictitious or just incidental?
In GR the gravitational force is considered to be equivalent (i.e. of the same nature) to an inertial force so in that sense you're correct. Howevever regarding this "real/fictitious" thing - Newton may have considered the Coriolis force to be 'fictitious' but Einstein considered it "real," i.e. Einstein wroteJimmy wrote
I've even heard gravity, within the context of general relativity, referred to as a 'fictitious' force.
Both A.P. French and Cornelius Lanczos consider inertial forces to be real as well.Can gravitation and inertia be identical? This question leads directly to the General Theory of Relativity. Is it not possible for me to regard the Earth as free from rotation, if I conceive of the centrifugal force, which acts on all bodies at rest relatively to the earth, as being a "real" gravitational field of gravitation, or part of such a field? If this idea can be carried out, then we shall have proved in very truth the identity of gravitation and inertia. For the same property which is regarded as inertia from the point of view of a system not taking part of the rotation can be interpreted as gravitation when considered with respect to a system that shares this rotation. According to Newton, this interpretation is impossible, because in Newton's theory there is no "real" field of the "Coriolis-field" type. But perhaps Newton's law of field could be replaced by another that fits in with the field which holds with respect to a "rotating" system of co-ordiantes? My conviction of the identity of inertial and gravitational mass aroused within me the feeling of absolute confidence in the correctness of this interpretation. Can gravitation and inertia be identical? This question leads directly to the General Theory of Relativity. Is it not possible for me to regard the Earth as free from rotation, if I conceive of the centrifugal force, which acts on all bodies at rest relatively to the earth, as being a "real" gravitational field of gravitation, or part of such a field? If this idea can be carried out, then we shall have proved in very truth the identity of gravitation and inertia. For the same property which is regarded as inertia from the point of view of a system not taking part of the rotation can be interpreted as gravitation when considered with respect to a system that shares this rotation. According to Newton, this interpretation is impossible, because in Newton's theory there is no "real" field of the "Coriolis-field" type. But perhaps Newton's law of field could be replaced by another that fits in with the field which holds with respect to a "rotating" system of co-ordiantes? My conviction of the identity of inertial and gravitational mass aroused within me the feeling of absolute confidence in the correctness of this interpretation.
Originally posted by Mk
I remember looking at a study done by students at the University of Michigan that said either centrifical or centrifigal force doesn't exist. Can someone clear that up?
Arcon: In GR the gravitational force is considered to be equivalent (i.e. of the same nature) to an inertial force so in that sense you're correct. Howevever regarding this "real/fictitious" thing - Newton may have considered the Coriolis force to be 'fictitious' but Einstein considered it "real," i.e. Einstein wrote...
Originally posted by Jimmy
Thanks for posting that Arcon. So gravity can be thought of as our inertial tendency to follow geodesics through space-time and the force I feel as weight on the surface of the Earth is an inertial force; the surface of the Earth is preventing me from moving along in a straight line (geodesic) through it's own space-time curvature.
Originally posted by Arcon
Don't think of it as "fictitious" since its just as 'real' as any other force. Refering to it as an "inertial force" is much better.
Originally posted by Arcon
The force the you exert on the floor is an inertial force. The force the floor exerts on you is not.
For example: Suppose in your living room there is a uniform gravitational field. Suppose also that there is an electric field in your living room which is in the direction pointing from the floor to the ceiling. Place a ball which is charged such that it floats. I.e. the gravitational force is equal and opposite to the electric force. Then the force on the charge due to the gravitational field is an inertial force. The force on the charge due to the electric field is not an inertial force.
I believe you can view (as you point out) the gravitational force as an inertial force, but the force you exert on the floor is not the gravitational force: it is a "real" electromagnetic force---your feet pushing against the floor.Originally posted by Arcon
The force the you exert on the floor is an inertial force. The force the floor exerts on you is not.
There is no other name for such a force other than "non-inertial force."Originally posted by Jimmy
I'm a little confused.
I understand the force of the electric field is not inertial. I also understand that the force I exert on the floor is inertial. What do you call the force that the floor exerts on me?
What's wrong with debate? That's part of what many physics discussions are.I promise I'm not trying to debate what you said. I really don't understand.
Originally posted by Arcon
There is no other name for such a force other than "non-inertial force."
What's wrong with debate? That's part of what many physics discussions are.
No, the centrifugal force is not considered a real force. It is actually an apparent force that arises from the inertia of an object moving in a curved path.
The term "fictitious" is used because the centrifugal force does not originate from a physical interaction between two objects. It only appears to exist because of the object's motion.
No, the centrifugal force cannot be measured directly. However, its effects can be observed and measured through other physical quantities, such as acceleration and velocity.
No, the centrifugal force and the centripetal force are two different forces. The centripetal force is the real force that acts towards the center of a curved path, while the centrifugal force is the apparent force that acts away from the center.
Yes, the centrifugal force is always present in circular motion. It is a result of the object's inertia and the curved path it follows, so it will always be present as long as the object is in motion.