1. Newton's First Law (Law of Inertia)
An object remains in a state of rest or of uniform motion in a straight line unless compelled
to change that state by an applied force. Inertia is the natural tendency of objects
to resist change in their state of motion.
2. Newton's Second Law
The rate of change of momentum of an object is proportional to the applied unbalanced force
in the direction of force. F = ma.
Momentum (p): The product of mass and velocity (p = mv). SI unit: kg m/s.
3. Newton's Third Law
To every action, there is an equal and opposite reaction. They act on two different bodies.
4. Conservation of Momentum
In an isolated system (no external force), the total momentum remains constant during a
collision. Total momentum before collision = Total momentum after collision.