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Table of Contents
Newton's Laws of Motion
1st Law
An object at rest tends to stay at rest.
In an inertial frame of reference, an object either remains at rest or continues to move at a constant velocity, unless acted upon by a force. Mathmatically defined as $F_{net} = ma$ where $F_{net} = 0$.
2nd Law
An object in motion tends to stay in motion.
In an inertial frame of reference, the vector sum of the forces $F_{net}$ on an object is equal to the mass $m$ of that object multiplied by the acceleration a of the object. Mathmatically the same as the first law: $F_{net} = ma$1), but where $F_{net} \ne 0$.
3rd Law
Every action has an equal and opposite reaction.
The third law states that whenever one body exerts a force on a second body, the second object exerts a force that is equal in magnitude and opposite in direction. $F_a = -F_b$. Note that it is the force that is equivalent. With the 2nd law, this means that they can have differing accelerations after the application of the force depending on mass.
