 Aristotle wrote that moving objects need a push or pull to stay in motion.  Galileo showed that moving objects would keep moving in a straight line with out a push or pull until something interfered with its motions.  Newton created the Three Laws of Motion by developing the laws from Galileo. Issac Newton Galileo Aristotle

An object in motion tends to stay in motion an object at rest tends to stay at rest an object in motion tends to stay in motion. Example: when a car is turning you turn when the car stops you stop

 Force= mass x acceleration For example, it is easier to kick a soccer ball over than a wall.

 For every action there is an equal and opposite reaction force. Example : When bumper cars bang into each other carrying the same amount of weight they move backwards.

 Friction is a force that opposes motion whenever two surfaces rub against each other a. Causes heat b. Slows object down

 The same in size, but opposite in direction. There is no change in motion with balanced forces because they are applying the same amount of force. For example, when two cars, equal in size, are leaning against but not falling because of how equal they are.

 Not equal in size, but somewhat similar in direction. Unbalanced forces will put enough force on an object in rest to move. For example, when two cars are leaning against each other, one car falls over because the other one doesn’t apply the same force as the other one.

 Force is a push or pull. A force can make an object slow down, speed up, or stop moving.  Motion is measured by the change of position of an object.

Q. Around three hundred years before Christ, what did Aristotle write? A. Moving objects need a push or pull to keep in motion. Q. What is the First Law of Motion? A. An object in motion tends to stay in motion an object at rest tends to stay at rest unless an outside force acts upon it. Q. What is Friction? A. Friction is a force that opposes motion whenever two surfaces rub against each other.