Inertia, Centripetal Force and Centrifugal Force

  What are Inertia, Centripetal Force and Centrifugal Force?

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Inersha

Resistance to change is called inertia. This term was first used by Galileo. If a body is stationary it will remain stationary and if a body is in uniform motion it will move it cannot change its position by itself. Any external force can change its state. But she herself cannot change her condition. Inertia is a property of a material object itself. This is the definition of energy.There are different types of inertia. Such as inertia of stationary state, inertia of motion, and inertia of direction etc. We will not highlight them because mentioning them here will make the post long. But what is worth mentioning here is the name of the measurement of mass inertia. That is, if the mass of the body is more, its inertia is more. And the body will be so resistant to changing its state.

Inertial observer and non-inertial observer:

In order to understand Centripetal Force and Centrifugal Force well, we need to see the frame of reference of the observer. A frame of reference is one in which the observer is either stationary or has constant velocity. Such a frame of reference is called an inertial frame of reference.

 Newton's laws are applied very accurately in this frame. We have to assume that no fictitious or fake force i.e. pseudo force is applied. The second frame of reference is non-inertial in that Newton's laws cannot be properly applied. And we have to apply a fictitious force called pseudo force. An observer in a non-inertial frame of reference is not stationary, and his velocity is changing i.e. he is observing from a location that is in circular motion. It is also called Accelerated Frame of Reference. And in such a frame of reference pseudo force has to be assumed. And this has to be assumed because Newton's laws can be welded. As the earth revolves around the sun,

 so if you look very technically then its frame of reference is also non-inertial but the interesting thing is, almost the acceleration is assumed to be zero. That is, it is assumed to be an inertial frame.

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Centripetal Force:

Suppose a planet is in motion, the motion of this planet is straight. All of a sudden you see that he has turned or crouched. This happened due to gravity. The inertia of the planet will try to keep it in straight motion and the gravity of the star will try to pull it towards itself. The result will be like this, it will not go straight or towards the star, but it will bend and make a circle. Here gravity acted as a centripetal force,

: because the force keeping it in circular motion is called centripetal force. It is not a new force, a force transformed into a centripetal force. And it looks towards the center. Another example is the very famous stone tied with a string. You tie a stone with a string, then with your finger create tension in the string, you will see that the stone will be forced to move in a circular motion.

Here the tension in the cord began to act as a centripetal force.

Now in this example our observer was standing still and watching. Which means no pseudo force has to be applied.

 Centrifugal force:

Many teachers do not like this force and concept. Even if he is a very good physicist. This is why

This is a pseudo-force. Which does not happen in reality. And those little mouths who are students of innocent minds like mine cannot grasp Newton's laws. Now you have to remember that observer thing. To understand this, think of swings. When we were children, there were many such swings at fairs. When you sit on the swing and take swings, you feel that nothing will throw you out. That thing is none other than pseudo force called centrifugal force.

If an observer is not in a rotating frame of reference then this force is not assumed. Because Newton's laws apply correctly to observers who are in an inertial frame of reference. The result is that if the observer himself is in a non-inertial frame, then the centrifugal force is assumed. If not, then centrifugal force is not assumed, even if there is no circular motion.

Confusion arises when some teachers teach that centrifugal force is directed toward the center and centrifugal force pushes the body outward. But repulsion is also assumed only when the observer himself is in a non-inertial frame. Explained quite well in the book given bellows why Centripetal and Centrifugal Force are not Pair?

Both of them are written as peer forces in many places even in class 9th physics book, but they are not. This is not because the centrifugal force does not exist in the first place, but we assume it for a non-inertial observer.

2. Peer forces never act on one body but they act on different bodies. This means that if we look at the centripetal force and the centrifugal force, they are applied to the same body. While in pair force, forces act on different bodies. For example, the sun exerts gravity on the earth, in turn the earth will exert gravity on the sun.

3. Peer force has the same nature. That is, if you push the wall, the wall will also push you. If an object exerts a gravitational force, the other body will also exert a gravitational force in return. This is not felt in normal life. But this is the truth. Now if you look at Centripetal Force and Centrifugal Force then it is clear that their nature is not the same.

4. Centrifugal force will be assumed only when the observer is in a non-inertial frame of reference. If the observer is not in a non-inertial frame of reference, then it is not assumed. Whether circular motion. Now the moon is also in circular motion. But there is no body there, so there is no centrifugal force on it. However, centripetal force is acting on it

 The direction of which is towards the center means towards the center of the earth.

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