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Newton's 3 laws are very important. A scientific law connot be broken. Newton's first law explains that an object in motion will stay in motion and will go in the same direction and the same speed untill a force is applied to it. It also says that an object at rest will stay at rest and not move until a force moves it. The reason a soccer ball stops is because friction between it and the grass is a force and it slows it down. The reason that a ball on the top of a hill rolls down is because the force of gravity pulls it down.
The second law says that an object will go in the direction of the net force. That means that when a plane flies even though gravity, air resitance, and wind are pushing the plane because the propulsion of the plane is stronger then those forces the plane will go up.
The third law says that for every action there is an equal and opposite reaction. This means that when you push down to jump your pushig down the same amout that you go up. The same thing happens when a rocket lifts off. It also means that while you are standing on the ground the ground is pushing you up the same amount that gravity is pulling you down. This makes it so that you don't sink into the ground.
Now for gravity. Gravity just says that everything attracts everything else. It also says that the larger something is the stronger the attraction. That is why you're strongly attrated to the Earth but an acorn on the ground isn't strongly attracted to you. Also the farther apart 2 things are the weaker their attraction toward each other. That is why you stick to the Earth and don't fly away to the sun even though the sun is much bigger. That shows that the strength of the gravitational pull depends on mass and distance.
You remember Galileo right? Well remember that expirement he did where he dropped two things of different sizes and they hit the ground at the same time. I'm just gonna restate that here because it was pretty important.
On the day that Galileo died Isaac Newton was born. Isaac Newton was an overachiever who decided to figure out what gravity really is. He figured out that all objects have a gravitational pull and they all are pulling on each other. He couldn't just stop after he discovered the laws of motion and invented calculus. He just had to also define gravity.
An object's mass isn't the same as it's weight. I say this a lot because a lot of people don't know this. An object's weight is how hard the planet your on pulls on you. While you mass is how much stuff is in you. This means that if you move to mars your mass won't change but your weight will.
Gravity is one of the most important forces in the universe. This is because it holds solar systems, galaxies, and planets together.
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1st and 2nd law
