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23 November 2024 20:58

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Question

Asked by: Victor Geere
Subject: Centripetal vs. Centrifugal
Question: Why are centripetal and centrifugal forces not equal?
Date: 6 May 2005
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Answers (Ordered by Date)


Answer: Eric James ----- - 07/05/2005 06:26:44
 Victor,

They are equal.

The force acting to hold the mass to the axis (centripetal force) must exactly counter the forces trying to rip the mass away from the axis (centrifugal).

In a gyro, most of the centripetal force is hidden in the molecular bonds of the material of which it is made.

With the moon and orbiting bodies, the centripetal force is simply gravity.

Think like this: If centrifugal force was greater than centripetal force, what prevents the moon from simply flying awayt?

Eric

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Answer: Victor Geere - 09/05/2005 08:31:17
 I knew you were going to say that. All the examples we can mention of stable systems are simply examples of where the centripetal and centrifugal forces are equal. But they aren't always equal, like if you attach a bearing to a flywheel with sticky tape and spin the flywheel hard enough, then the bearing will fly into the distance. Centripetal force is not the oposite equal of centrifugal force as the one does not increase with the other. ...so my point is that even a static flywheel that is not in precession mode might be used to bend a force at a 90 degree angle. ...or convert a angular force into linear etc.

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Answer: Eric James ----- - 10/05/2005 03:39:11
 Victor,

Ah, but they are equal. That is until separation occurs.

In your taped weight analogy, the tape's glue forms a molecualr bond with the flywheel. This bond has a strength of a certain value. Spinning the flywheel to a speed where the weight's desire to travel in a straight line exceeds the tape's bonding (centripetal force) ability to hold on to it, is the point of separation.

When this occurs, you no longer have a centripetal force to speak of, nor a centrifugal effect. So, the question becomes null and void.

Also, centripetal force actually does increase in a molecularly bonded material with the rate of rotation up to the point that the material reaches its limits and fragments.

Basically, the electromagnetic bonds beween the atoms and molecules of the material get stressed and stretched during rotation. The faster you rotate the mass, the more stretching and stress the material experiences until it reaches fragmentation.

Then, once again, you no longer have centripetal force and centrifugal effects to speak of.

Eric

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Answer: Victor Geere - 10/05/2005 09:18:16
 OK, so centripetal force is a vector pointing towards the axis of spin and only becomes measureable under the influence of centrifugal force and equals centrifugal force for as long as both exist?

The unbalanced force, the amount of force that causes the bearing to eject after centripetal force has been overcome, is an example of angular momentum being turned into linear momentum, which is something to think about. Strictly speaking this unbalanced force is not centrifugal force, because this unbalanced force is born when centrifugal (and centripetal) force dies. Yet it received it's value while still under the influence of centrifugal force. If centrifugal and centripetal forces are equal, what would this residual or unbalanced force be called.

Another thing, if centripetal force increased with centrifugal force, the bearing would never eject. If there was no sticky tape, the bearing will almost immediately eject. I can only conclude that centripetal force is not a function of centrifugal force. The two are not oposite equals. Centrifugal force is a function of rotation, radius and mass. Centripetal force has got nothing to do with any of that. It is a function of molecular, magnetic or gravitational bonding. Ok, gravity is a function of mass, but centrifugal force can still be increased beyond centripetal force, a prerequisite for the bearing to eject. The question does not become null and void, the bearing still has momentum, a function of force and mass. I need to know what that force is if centrifugal force has been equaly oposed by centripetal force.

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Answer: Glenn Hawkins - 10/05/2005 15:41:10
 Eric and Vector,

I reserve interfering with my conclusions and the explanations for them. I’m more interested in following the catfight that is about to begin.

I have read some post by Victor. I am sometimes able to recognize his conclusions are both, most unique and right, because some have reflected precisely in alignment with the mechanics I have researched. As to the ability of Eric, I have known about this for a long time. I predict that the first thing each of you will do is vastly underestimate the tenacity and power of the mind of the other. You two are well paired. As you proceed through these strings each of you is in for it. You just don’t know it yet. You’re very different. I wonder if you can ever agree on anything. It should be interesting.

Glenn Hawkins


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Answer: Glenn Hawkins - 10/05/2005 17:05:07
 Very well. I’ll inter…just a little bit.

Neither centrifuge, nor centripetal are true forces. Both are forms of pressure. The major difference is that centrifuge is produced by the constant inertia changes occurring in rotation and in all instants where matter is traveling in a curvature. Centripetal on the other hand is an inherent potential within the molecular structure of material that you speak about. The potential to withstand force can neither be increased, nor decreased. How much of the potential is used is determined by how much centrifuge is present. THIS IS VERY DIFFERENT THAN IS TAUGHT. Both centrifuge and centripetal are generated pressure responses to one another caused by actions, but they themselves are not actions, and neither are they true forces for they cease to produce a consequence when freed to do so. The two pressures are always equal to one another (Just as actions and reactions would be) so long as the inherent potential of the binding material remains unbroken.

This can get complicated. I hope some day to explain my understanding at length, but with economy. Certainly, certainly not the stacks of pages I have on the subject.

Glenn,


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Answer: Victor Geere - 11/05/2005 09:15:25
 >> " for they cease to produce a consequence when freed to do so"

So what is the force called that causes the bearing to eject?

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Answer: Glenn Hawkins - 12/05/2005 00:15:52
 Hi Victor, how are you doing today? I hope we’re all happy and fine today of course and doing swell.

You want me to say centrifuge. You want me to say centrifuge pulls the bearing away. Ok, CENTRIFUGE, CENTRIFUDGE, except that’s not the point.

You can say centrifuge overwhelms the balance between it and centripetal, or you can say a break in centripetal occurred. Ether way the grip on the bearing is loosed and the bearing is freed to travel away in a direction that will be in a PERFECT RIGHT ANGLE TO THE ALINEMENT OF CENTRIGUGE AND CENTRIPITAL. This happens the instant the paired oboist twins cease to exist. Centrifuge exerts no after-separation directional force at all, none, zilch. The pair, C&C is finished. Neither gives any energy to the bearing, they never did, except the bearing was once under their opposite pressures. The energy of the ball to fly away from rotation comes from the energy in rotation, which comes from the energy that caused rotation. The separation is a release on energy contained, not a creator of energy. Ahh! Rotation. OK, I will teach you something in a way you can understand and believe and that so far as I am able to determine no one knows about. Well… maybe later. Good talking to you.

Glenn Hawkins,


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Answer: Eric James ----- - 12/05/2005 04:17:10
 Victor,

Glenn understands it properly, although his terms aren't scientific.

Centripetal force is considered to be a "real" force because it works that way mathematically.

Basically, to change the direction of a mass in motion is an acceleration in a new direction. According to Newton, all accelerations require force. Therefore, centripetal force is a real force.

Centrifugal force is not real because it is a result of centripetal force. It is not causing anything to accelerate, therefore there is no "real" force to speak of mathematically.

Since centrifugal "force" is a result of centripetal force, they are inexorably linked. That is they are balanced in an angular momentum situation. They cease to exist when rotation ceases.

Therefore, when the ball-bearing leaves the flywheel, they cease to exist (in relation to the combined flywheel/ball-bearing system.

Angular momentum continues to exist as a relation to the vectors between the two separating bodies, but not centipetal force or the centrifugal effect.

Also, when the ball-bearing breaks away, there is an opposite and eqaul reaction to the flywheel in the other direction (with an angular offset).

Eric

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Answer: Glenn Hawkins - 12/05/2005 05:12:14
 Well, what the hay. I keep treating to explain the mechanical truth in the ‘how’ and ‘why’ or rotation. For a year I rambled about it not having been explained correctly. I would have a long and complicated piece to write with many hand drawn pictures. I’ve done much already, but it’s just a great jumble of too many pages. Those who know the most would be the most surprised because they would believe me. But unless I ever determine to do it I suppose I should just shut up. Yeah I understand. And Eric understand perfectly well too and that will do for now. At least until I get struck by lighting or something another that will set me to work in explaining the intricate beauty of live centrifuge, yet unknown to science. I have created new knowledge. I can’t argue in support of it until I do it, so now I am shutting up about it. But Eric, you are wrong about centrifuge just like everybody else on earth. But you are in good company. And your explanation is as always excellent.
Glenn H.


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Answer: Victor Geere - 12/05/2005 12:44:56
 Eric
>>"Basically, to change the direction of a mass in motion is an acceleration in a new direction. According to Newton, all accelerations require force. Therefore, centripetal force is a real force."
So where does centripetal force accelerate the bearing to. I don't see any acceleration in the direction of centripetal force. But if I change my mind and believe you, I don't see any acceleration in the direction of centrifugal force either. So are they both energy as opposed to force. Mostly potential energy that could become kinetic energy? The same energy that gets stored in a gyroscope and tapped during precession?


Glenn,
>>"But Eric, you are wrong about centrifuge just like everybody else on earth"
Does that include you? Einstein and Newton can't agree, so one has to be wrong, or both. Or we don't have the full story. Amazing isn't it? Good luck with the writing.

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Answer: Eric James ----- - 14/05/2005 01:02:48
 Victor,

The acceleration isn't making the rotation go faster, it is making the rotation period.

Imagine your bearing moving in a straight line in space at the same velocity it has on the gyro. How would you turn it from that direction without applying force?

The answer is you can't. To turn an object in motion requires force and as such it is an acceleration.

Even though turning an object appears not to add momentum... it does, only its in a new direction.

Where before you turn an object it has momentum in one direction but none (zero, nada, zilch) in the direction you intend to turn it. Applying force to turn it now gives it momentum in the new direction. That is it is now proceeding on a path in the direction of the turn with more than zero momentum in this direction.

Glenn, centerfuge can act like a force in many ways, although it isn't. I look forward to hearing more from you on this.

Eric

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Answer: Glenn Hawkins - 14/05/2005 01:34:53
 Excellent, Victor. Go to the new tread, ‘What is Archulation?’ There is our beginning.

Eric, did you say: “Glenn, centrifuge can act like a force in many ways, although it isn't….”

As to the mechanics only, I am reminded of the lyrics of the old Buster Brown’s - harmonica & vocal, “Well now, is you is, or is you ain’t my baby?” He wanted to know, is it is, or is it ain’t a force. He didn’t want to know is it acts like what it ain’t. Is it is, or is it ain’t? Just foolin’ around. Try the new string. I worked hard on it. I hope you approve of it.




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Answer: David Thomson - 21/09/2007 22:51:13
 Centrifugal force is a true force.If a mass moves in a circular path it is being accelarated
towards the axis of rotation.The centrifugal force is the force produced by the mass by this accelaration. F=Ma .The centripetal force is the force which causes the mass to move in a circular path as opposed to linear motion.In a sence the centrifugal force is the
EQUAL and oppisite reaction to centripetal force.

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Answer: Glenn Hawkins - 22/09/2007 04:03:35
 Absolutely.

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