Centrifugal Force: Get Logical Explanation

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Discussion Overview

The discussion revolves around the concept of centrifugal force, particularly in the context of circular motion. Participants explore the nature of forces experienced by objects in rotating systems, including theoretical explanations and practical examples such as a coin on a rotating disk and a person in a rotating rotor.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • One participant expresses confusion about why an object appears to be thrown outward in circular motion, questioning the nature of the forces involved.
  • Another participant states that a force is necessary to change an object's direction, implying that this force is felt during circular motion.
  • A different viewpoint asserts that centrifugal force does not exist, suggesting that the sensation of being pushed outward is due to the absence of a force rather than the presence of one.
  • One participant clarifies that what is actually felt is the centripetal force, which is the force exerted by the wall of the rotor in the example provided, emphasizing the role of inertia in circular motion.
  • It is noted that centrifugal force is considered a fictitious force that arises in non-inertial frames of reference, and that real forces must be accounted for when applying Newton's laws in such frames.
  • Another participant agrees that centrifugal force is not a real force but acknowledges that its effects can be observed in rotating systems.

Areas of Agreement / Disagreement

Participants express differing views on the existence and nature of centrifugal force, with some arguing it is fictitious while others discuss its effects in non-inertial frames. There is no consensus on the explanation of the outward force experienced in circular motion.

Contextual Notes

The discussion highlights the complexity of forces in rotating systems and the dependence on the frame of reference used to analyze the motion. Assumptions about the nature of forces and the definitions of centrifugal and centripetal forces are not fully resolved.

Wiz
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hi,
we all know tht when a body moves in a circular path,it experiences an outward force(eg:a coin on rotating disc gets thrown outward).Theoritically fine.But can anyone give me the LOGICAL explanation for this?Wht does it get thrown outward?

Also consider a person in a rotar standing with back touched to its wall...when the rotar starts rotating and the floor is moved down,the person does not fall since his weight is balanced by the frictional force which depends on the normal force.Which means that the person is exerting a force on the wall of the rotar..if centrifugal force is fictious then which force is this?..I am so deeply confused..
wiz
 
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A force is required to change the direction of an object (make it move in a circular path). That's the force that is felt.
 
There is no such thing as centrifugal force, its rather the lack of force that is felt.
 
What you actually feel, as Russ indicated, is the centripetal force that keeps you moving in a circle. In the rotor example, you feel the wall pushing against you--centripetal force. All this is perfectly understandable when viewed from the usual inertial frame; Newton's laws demand it.

The coin on the rotating disk is equally understandable: To keep the coin in place on the rotating disk requires a certain centripetal force; if the friction is insufficient, then the coin will tend to slide along its direction of motion. Inertia (Newton's 1st law) in action.

The so-called "fictitious" forces arise when one views things from a non-inertial, accelerating frame. In such a frame, Newton's law's don't apply without modification. The modification needed is the addition of inertial forces. In the rotor example, the wall exerts a "real" force against you ("real" just means that there is a real agent producing the force: the wall). To apply Newton's laws from the view of the rotating frame you must include the centrifugal force acting outwards: coupled with the force of the wall, the net force is zero.

But Eivind is correct that centrifugal force doesn't exist as a real force, it is only an artifact of using a noninertial frame of reference. But the effects are quite real.
 

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