What is gravity?
Do you really understand gravity?
Gravity is a force pulling together two bodies of matter. Matter is basically the total amount of mass of an object. It is one of the universal forces in nature. The effect of gravity can be seen best when one object is large and one small. The bigger the object or body of matter; the stronger the gravitational pull. However, when a large object is farther from the smaller object the gravitation becomes weak. This causes the two objects or bodies of matter to break apart.
Gravity exists in more than just space. It exist in every part of our day to day life. Yes, gravity does keep the the planets in orbit around the sun and it does keep the moon orbiting around the earth. However, space is not the only place for gravity. Have you ever heard of the say "What goes up, must come down". Sure you have. This is exactly what gravity does. Let's say you go outside and decide to bounce a ball on the concrete. What happens? The ball suddenly goes up but then directly falls to the ground.
Why is this? This is because when you first bounce the ball the energy going up is considered gravitational potential energy (GPE). Then the ball begins to fall because the GPE is forcing the ball to go back down toward the ground. When this happens, the energy turns into kinetic energy. This all relates to gravity and something as simple as bouncing a ball is because of gravity.
Today there are more theories about gravity but the main two men that came up with the idea of gravity are Sir Isaac Newton and Albert Einstein. I am sure if you have attended school then you have heard about both of these scientists. I won't go too much of the history or the theories itself, but will briefly tell you the differences in their theories.
In 1687, Sir Isaac Newton published his theory of gravity called the Universal Law of Gravitation. Newton believed that gravity was universal and was not only in space. Meaning all objects will attract each other from this force called gravity. This is one reason why his theory is so important. He believes the farther away the objects are the weaker the gravitational pull.
Albert Einstein in the 1900's came up with a theory about gravity and it was found in the General Theory of Relativity. Einstein's theory was very different compared to Newton's theory. Einstein believed that gravity wasn't really gravity, it was like the "fourth dimension". It was distorted in the shape of space-time. An example would be to think of space-time as a piece of rubber with a bowling ball on top of it. The area around the bolling ball would distort the rubber and the heavier the object the more the distortion appears. This is basically what Einstein thought about gravity.
Gravity is invisible to our eyes. You can not physically see gravity. You can see the effects of gravity everyday. Hope this better explains gravity to anyone that didn't quite get it. Peace, love, and blessings!