Chapter Eight, Lesson Three: Newton's Laws of Motion

Newton’s first law of motion states that an object at rest will remain at rest unless acted upon by a nonzero net force. An object moving at a constant velocity will continue moving at a constant velocity unless acted upon by a nonzero net force.

Resistance to change in motion is called inertia.

Newton’s second law of motion states that an object’s acceleration depends on its mass and on the net force acting on it.

Newton’s third law of motion states that if one object exerts a force on another object, then the second object exerts a force of equal strength in the opposite direction on the first object.