Newton’s Laws:
- 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.
- The change of motion of an object is proportional to the force impressed; and is made in the direction of the straight line in which the force is impressed.
- To every action, there is always opposed an equal reaction; or, the mutual actions of two bodies upon each other is always equal, and directed to contrary parts.