An introduction to motion and its application to Space Rails
Asides being one of the fundamental concepts of modern physics, the concept of motion is what we can observe easily around us. Virtually everything in the environment is in motion and motion, in fact, is what keeps the world going. Have you ever thought about what is responsible for day and night? I bet you thought the sun shines during the day and rests at night, or something close to that. But that is far away from the answer.
Explaining the occurrence of Day and Night
Though it may seem very difficult to believe, the earth that we live is in constant motion. And it’s not even a single type of motion at that. The earth rotates around the sun and also rotates about its own axis. That could be a tad difficult to understand right? Well, think of the earth as a soccer ball (you wouldn’t be too wrong as the earth is essentially a very large ball). If you decide to move the ball around the center circle, there’ll be two kinds of motions. First the movement of the ball around that point and then the movement of the ball about its own axis.
If you want to observe this, you could color different points on the ball differently. You would see that if you began rotating the ball with the redpoint facing up, the red point may be facing the sides by the time you get back to the former position. That is exactly what happens when the earth moves, except both movements, are strictly coordinated. It is the earth’s rotation about its own axis that takes our own part of the world away from the sun and that is when night occurs. It also accounts for why day and night do not occur at the same time everywhere in the world. When our side of the ball is facing the sun, some other side would be blocked from it.
What causes motion?
We already have a hint of just how important motion could be in our environment. But what causes motion? There is another simple answer to this. And it is 'force'. Force is essentially what drives motion. Before a car can move, a force has to be applied. Before a piece of paper can fall off the table, a force must have disturbed it.
A famous scientist, Sir Isaac Newton studied the relationship between force and motion and his conclusion were summarized as Newton’s laws of motion. To this day, the three laws of Newton are still extensively studied and it forms the foundation upon which many discoveries are made. In the next series, you’ll be learning about the laws of motion and how you can observe these laws via space rails.