What is Gravity? (A Simple Explanation)
Gravity is the force that keeps things together. It also is the force that makes things fall to the ground when dropped.
While Isaac Newton didn't "discover" gravity, he was the first person to really understand what gravity was. In the famous apple drop incident, Newton realized that an apple would always fall from the tree and not float up into the atmosphere. He also realized that this invisible force (gravity) is what holds us to the planet and keeps us from floating around too.
Newton's "law of gravity" describes how things are held together, and how things are attracted to each other. According to Newton, everything "that has mass also has gravity and is tugging on everything else that has mass" (CCMR). He also realized that the larger the mass the stronger the gravitational pull something has.
Simply put, the earth has a larger mass than the moon does, and as such has a stronger gravitational pull than the moon. As we walk on the earth, gravity pulls our feet to the ground. But when people walk on the moon they tend to bounce more, the gravitational pull is weaker on the moon than is is on earth.
Check out the brief video below for a description of what gravity is, and how it works.
Based on our surroundings we have a pretty good idea of how gravity works. Drop something light and it falls slower than something that is heavy.
But have you ever wondered if gravity is different anywhere else, such as the moon where there is less gravity?
Just how does gravity work (or what does it look like) in space where there is little gravitational pull?
You Try It!
Conduct a small experiment at home to see how gravity works, then check out the video below and see how the same experiment would yield different results in space (where there is no gravity).
Saturate a washcloth with water.
Hold the wet washcloth over a bowl (or the sink).
Wring the washcloth and watch what happens to the water.
You should notice that the water falls down into the sink, that's because the water's mass is attracted to the earth.
How you ever wondered what would happen to the water in a place where there was no gravity to pull the water down?
Go ahead and watch the video below and see what happens when a wet washcloth is wrung out in space. You'll be amazed at what happens!