Hello and Today I'm going to talk about FrictionGravityMassBalanced/Unbalanced ForceNewtons Laws of Motion If there were no friction, we wouldn't be able to stop ourselves. Since Ice has low friction, it's hard to stop ourselves easily. Friction is what stops an object, for example: If I try to slide n cement, I wouldn't be able to because friction is stopping myself from sliding. Without gravity, everything would all float into space! Gravity is what pushes things down to the ground, that's why we're still on earth right now! When a rock falls, gravity is pushing it down to the surface. That's why the rock is falling down, because gravity is pushing it downwards. Imagine a world without gravity. Gee, we wouldn't last very long... Mass is how much something weighs, for example: I can push my sister on the swing because she has less mass, I can't push my mom because she has more mass than me and my sister combined. I remembered when I lift myself up to see if I could lift my own weight, I could! A balanced force is when two forces are putting the same amount of force on one object. For example, a tug of war battle. If both sides are pulling the equal amount of force, then nothing happens. An unbalanced force is when one person is pushing more than the other person. Let's use tug of war as an example again! If one side is pulling more force than the other, that side will most likely win, unless the other side let's go of the rope. :P Newton's third law is, every object has an opposite and equal reaction. For example: if I hit a softball onto the ground, that's my opposite reaction. When the ball goes up, that's the qual reaction. Newton's first law states that every object will not move unless an outside force acts upon it. Every object will not stay in motion unless an outside acts upon it. An example of newton's first law would be a kicking a ball. At first, the ball is at rest and doesn't want to move. The ball will continue to stay put unless an outside like you will move it. When you kick the ball, the soccer ball is in motion and will keep staying in motion unless another outside acts upon it. (Grass, net, ground, etc...)Newton's second law is mass x acceleration. For example, moving a couch wth two different types of people on it. Say if a couch had a small dog on it, it would be easier to move since the dog has less mass, so it will allereation faster. How about a grown up dog. Since the grown up dog has more mass, it won't allecrate. as much since it's heavier.