Newton's First Law of Motion, also known as the Law of Inertia, states that an object at rest will remain at rest, and an object in motion will continue moving at constant velocity in a straight line, unless acted upon by an external force. This means objects naturally resist changes to their state of motion.
Newton's Second Law states that the force acting on an object equals its mass times its acceleration, written as F equals m a. This means that the acceleration of an object is directly proportional to the net force applied to it, and inversely proportional to its mass. The direction of acceleration is the same as the direction of the applied force.
Newton's Third Law states that for every action, there is an equal and opposite reaction. This means when object A exerts a force on object B, object B simultaneously exerts an equal force in the opposite direction on object A. These forces are equal in magnitude but opposite in direction, and they act on different objects.
Newton's laws appear everywhere in daily life. The first law explains why passengers lurch forward when a car brakes suddenly - they continue moving due to inertia until the seatbelt provides an external force. The second law is seen when pushing a shopping cart - a heavier cart requires more force for the same acceleration. The third law is demonstrated when walking - your foot pushes backward on the ground, and the ground pushes forward on your foot, propelling you forward.
In summary, Newton's three laws of motion provide the fundamental principles governing how objects move. The first law describes inertia - objects resist changes in their state of motion. The second law quantifies how force creates acceleration proportional to mass. The third law states that forces always come in equal and opposite pairs. Together, these three laws form the foundation of classical mechanics and help us understand motion in our everyday world.