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Newton's First Law states that an object will maintain its state of rest or uniform motion unless acted upon by an external force.On a perfectly smooth surface, with no friction or external forces, an object in motion will continue moving at a constant velocity.The ball maintains its velocity, neither speeding up nor slowing down.Let's see how inertia affects passenger safety in a car.When a car is moving, both the vehicle and passenger are in motion.If the car suddenly stops, the passenger's inertia causes them to continue moving forward. The seatbelt prevents this forward motion, keeping the passenger safe.The amount of inertia an object has is directly related to its mass.When the same force is applied to objects of different masses, the object with less mass experiences more change in motion.We see Newton's First Law at work in many everyday situations.Objects tend to maintain their state of motion or rest in various situations, from books staying on shelves to liquid staying in a moving cup.Newton's Second Law states that the net force acting on an object equals its mass times its acceleration.Let's understand the relationship between force, mass, and acceleration.Let's see how mass affects acceleration when the same force is applied to different objects.When we apply the same force to a lighter car, it accelerates more than a heavier car.If we double the force on the same object, the acceleration doubles as well.Remember: increasing force increases acceleration proportionally, while increasing mass decreases acceleration proportionally.Newton's Third Law states that for every action force, there is an equal and opposite reaction force.When we walk, we push down on the ground with our feet.The ground simultaneously pushes back up on us with exactly the same force.Rockets provide a perfect example of Newton's Third Law in action.As the rocket expels exhaust gases downward with a strong force......there is an equal reaction force pushing the rocket upward.A compressed spring demonstrates equal and opposite forces perfectly.When the spring is compressed, it pushes on both blocks with equal force in opposite directions.Magnetic forces also demonstrate Newton's Third Law.When two magnets interact, the attractive or repulsive forces are always equal and opposite.Newton's Third Law appears in many everyday situations. Here are some common examples of force pairs: