Why does the Earth keep spinning?

 "Why does the Earth keep spinning?" 

Inertia is the correct answer. 

The ability of a thing to withstand changes in motion. Newton's first law is only applicable to constant speed in a straight line, not too curved paths. Okay, so simply stating "inertia" is a dismissive response to this subject.

We need to take a closer look. If you enroll in an introductory physics course, your professor is likely to tell you something along the lines of Moving from one location to another necessitates the use of a set of measurements that are guided by a set of rules. 

Going around and about requires a distinct set of measurements, which are governed by a different set of criteria for each subsequent rotation. On the other hand, I made a very crucial point in a prior video: If your rule is subject to exceptions, it is not a particularly good rule.

 In physics, one of the goals is to develop better laws with fewer exceptions, and we do a very good job of it. These laws are applicable to both types of motion, in fact. Because of the way they are written, they are not very convenient. 

Let's start with something that appears to be straightforward. That's nothing more than a ball! You weren't even asked! A tennis ball, according to my clone, is what the majority of you see when you look at this. 

But it's much more than that, in my opinion. This ball is comprised of a rubber shell that is wrapped with nylon felt and that contains an air pocket inside it. Each of those materials is composed of molecules, which are composed of atoms, which are composed of subatomic particles, 

some of which are composed of even smaller particles, which are simply excitations in quantum fields, which are kept together by particle interactions, to form the material. All of this is done in order to create this item known as a tennis ball. Okay, that was a touch too in-depth. 

My point is that everything, including the Earth, operates in this manner. Because rotating objects are made up of many components, it is necessary to consider them as such rather than as a whole in order to comprehend how these rules apply to a rotating object. 

Each layer of the Earth is made up of a variety of different substances, and because of the force of inertia, all of the little pieces are trying to move in a straight path as much as they can. 

The Earth would do this if they were given the opportunity. We are aware that this is not the case, thus there must be another factor at play. Newton's first law states that anything moving in a straight path will continue to proceed at a constant pace until it encounters a total or imbalanced force from the outside. 

In order for certain sections of the Earth to not be doing this, there must be some sort of force preventing it. Newton's second rule of motion tells us that an unbalanced force is creating an acceleration at this point. 

Acceleration? However, its speed remains constant: Every 24 hours, there is one rotation. Ah! Acceleration, on the other hand, is more than just a shift in speed. "Acceleration" is defined as a change in "velocity," which includes a change in direction as well. 

If the force from the road is in the same direction as a car's motion, it will accelerate ahead and accelerate faster than it would otherwise. Upon impact, the ball is only partially accelerated in the direction of motion, causing it to slow down and accelerate while changing its direction at the same time. 

The result of circular motion is achieved when the force is never directed in the direction of the motion. The speed never changes, either up or down. The force merely alters the direction of the object. 

While the Earth is spinning, the same thing is happening to different places of the planet. However, it is still a significant acceleration. Moreover, it is a result of subatomic particle interactions, intermolecular forces, and, on a grander scale, gravity. 

However, when attempting to characterize the motion of a ball or the Earth, it is not necessarily necessary to take into account the momentum and energy of its constituent pieces, as well as the forces acting between them. 

Sometimes all you want to say is, "Wow, that's a ball." As a result, we disregard all of the forces that just change direction and refer to them as "rotational inertia." Any forces that cause a change in speed are multiplied by a distance and are referred to as torque. 

You'll end up with something that looks and functions very much like Newton's second law. Even while attempting to be practical, it can be easier to simply pretend and follow a different set of rules when trying to be realistic. 

It's common for science teachers to dismiss issues like this as uninteresting or unimportant. Do you have any that make you crazy? Please post your question in the comments section.

 Thank you for taking the time to read this article. If you'd like to see more, please consider subscribing. And, until next time, remember that it's perfectly acceptable to be a bit insane.