Centripetal and Centrifugal Forces

In summary, the conversation discussed the concept of centrifugal and centripetal forces in circular motion. It was mentioned that centrifugal force is not a real force, but rather an effect of inertia. The theory of General Relativity was also brought up, which states that there is no preferred frame of reference. The conversation also touched on the difference in equations of motion when viewed from different points of view. The speaker also mentioned a more in-depth discussion of the topic in their journal. Finally, the conversation concluded with a clarification of the question and a thank you to Marlon for their response.
  • #1
chunkymonkey
2
0
In class, I was told that the "centrifugal force" is merely an effect, and I can dig that. However, isn't the supposed "centripetal force" in actuality also merely an effect?
 
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  • #2
A quick search on google.com uncovers 437,000 various web pages to your question. Please look at least one over to clear up any confustion that you may have.
 
  • #3
Thats mean, he came here for help.

Centrifugal force isn't a real force, it does not play any role in circular motion.

The centripetal force is THE force of circular motion, it is the force that is of just the right magnitude (mv^2/r) to keep you going in a circle at a given speed.
 
  • #4
The theory of General Relativity was born in 1915 and its father is Albert Einstein. The basic postulate is that there is no preferable frame of reference what so ever. So basically the concept of an inertial observer is banned and every observer needs to be treated equally.

For example when an inertial observer looks at a spring that is making a circular orbit around him. He will write down the law of Hooke in order to describe the spring. But a non-inertial observer, moving along with the spring, will have extra terms in this equation that have nothing to do with the spring but with the fact that he is NOT inertial.

These extra terms can come from the fact that this frame of reference itself, is making a circular motion, for example, so there is a constant centripetal force that works onto this reference frame. Though the non-inertial observer moving along with the spring, and being submitted to the spring force; will write ma' = -kx. This means that the non-inertial observer is basically hanging like a block on the spring so the spring works on the observer.


But this is incorrect because there is also the centripetal force mv²/R. this force is a socalled pseudo-force for the non-inertial observer and he must write : ma' = -kx –mv²/R. This is correct because the inertial observer would have written ma = mv²/R = -kx. This is the second law of Newton for a spring in circular motion. Basically what we see here is a manifestation relativity, meaning that equations of motions are different when we change our point of view. It really depends on how we look at things. Basically a' =a -a_0 where a_0 is the acceleration of the non-inertial frame with respect to the inertial frame.

This equation states that the non-inertial force or acceleration (a') is equal to the inertial force or acceleration (a) without this influence of the motion of the non-inertial frame (-a_0). The inertial force is here -kx and it denotes the correct physical laws...


read my journal (page 8, 'the string theory part 1' entry) for more indept info


regards
marlon
 
  • #5
Well, I’d like to first say that it’s interesting to see how people response when one’s language is less erudite than one typically uses in speech. The intention of utilizing slang was more to mask my question from my science teacher who frequently replies to homework questions. Nonetheless, my question did go beyond the rather elementary concept of circular motion resulting from an inward-pointing force as opposed to an outward-facing one. In actuality, I am not a buffoon as Shockwave foolishly assumed, and I appreciate Whozum’s defense of the question; it is funny how an incoming MIT physics major can be misinterpreted. I would like to thank Marlon for his/her intelligent response; it was exactly what I was looking for.
 
  • #6
The centrifugal effect = Inertia. Think about that.
 
  • #7
A more fruitful search may be the one in PF. This exact topic has been discussed in depth extensively on the forum. Search around for additional information if you like, and post any follow-up questions you may have.
 

1. What is the difference between centripetal and centrifugal forces?

Centripetal force is the force that keeps an object moving in a circular path, directed towards the center of the circle. On the other hand, centrifugal force is a fictitious force that appears to act on an object moving in a circular path, directed away from the center of the circle.

2. How are centripetal and centrifugal forces related to circular motion?

Centripetal force is required for an object to maintain circular motion, as it constantly changes the direction of the object's velocity. Centrifugal force is the result of this change in direction, and it is equal in magnitude but opposite in direction to the centripetal force.

3. Can centripetal and centrifugal forces act on the same object at the same time?

No, centripetal and centrifugal forces cannot act on the same object at the same time. Centrifugal force is a fictitious force, meaning it only appears to exist in a non-inertial reference frame. In an inertial reference frame, only the centripetal force is present.

4. What are some examples of centripetal and centrifugal forces in everyday life?

Some examples of centripetal forces include the force of gravity keeping planets in orbit around the sun, the tension in a string keeping a spinning top in motion, and the friction between a car's tires and the road as it makes a turn. Examples of centrifugal forces include the sensation of being pushed outward when making a sharp turn in a car, the water being flung outwards from a spinning bucket, and the outward force experienced on a roller coaster loop.

5. How do centripetal and centrifugal forces affect the stability of an object in circular motion?

Centripetal force is necessary for an object to remain in stable circular motion. If the centripetal force is too weak, the object will fly off in a straight line. Centrifugal force can also affect stability, as it can cause an object to wobble or lose balance if it is too strong relative to the centripetal force.

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