Sir Isaac Newton: Three Laws of Motion
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- Law: a well established idea in science and one that can be used in many ways.
- Mass: the property of matter that makes it hard to change motion.
1. Every body continues in its state of rest, or of uniform motion in a straight line, unless it is
compelled to change that state by forces impressed upon it.
What was that? Look at it this way.
Things only change motion if there is a force acting on them. Such as pushing or pulling.
2. The acceleration of a body is directly proportional to the net force acting on the body and
inversely proportional to the mass of the body and is in the direction of the net force.
What? Think of it this way.
The amount of change in motion is less for big things than for small things. The second law says it is easier to push the empty cardboard box your refrigerator came in than the refrigerator.
3. Whenever one body exerts a force on a second body, the second body exerts an equal and
opposite force on the first.
In other words... You cannot push on an object without that object pushing on you.
Sometimes this law is explained as "to every action there is always an opposed equal reaction."





