Presentation on theme: "Gravity and Free Fall By: Christin Thrash. The Law of Universal Gravitation. This law states that all objects in the universe attract each other through."— Presentation transcript:
The Law of Universal Gravitation. This law states that all objects in the universe attract each other through gravitational force. It can be written mathematically: Force = Gravity(m1m2 divided by d squared). The equation says that the gravitational force increases as one or both masses increase.
Basic Facts Gravitational force will decrease as the distance between the masses increase. Even a little change in distance makes a huge difference because distance is squared in the equation. It does not matter if the object is big or small there is still a gravitational force between them. The larger the mass the more easier it is to detect a force.
Examples of gravity. Take an apple for instance. When an apple falls from a tree it is because the gravitational force between the earth and the apple is greater than the force between the apple and the tree. An elephant and a cat which one will have a greater gravitational force between the earth? The elephant will because the elephants mass is greater than the cats mass.
Free Fall When gravity is the only force acting on an object the object is in free fall. Free fall acceleration is directed toward the center of the earth. The acceleration is approximately 9.8 m/s/s. Free fall acceleration results from gravity, it is often abbreviated as the letter g.
Basic facts When air resistance is absent all objects near earths surface accelerate at the same rate regardless of their mass. Weight is equal to mass times free- fall acceleration or w = mg. Your weight is simply the amount of gravitational force exerted on you. Mass is the measure of the amount of matter in an object and weight is the gravitational force an object experiences because of its mass. The weight of an object depends on gravity so a change in an objects location will change the objects weight. Gravitational force influences the shapes of living things.
Examples of free fall An example of free fall would be a space craft in space. Because gravity is the only resistance on the craft it is considered to be in free fall.