2Newton’s Second Law of Motion The net force acting on an object causes that object to accelerate in the direction of the net force.Greater the force = Greater acceleration.FF
3Newton’s Second Law of Motion Inverse relationship between mass and acceleration!!!The greater the mass, the more force it takes to accelerate an object at the same rate of a less massive object!!!FF
4Newton’s Second Law of Motion The relationship between force, mass, and acceleration is expressed as:F = maSI unit = kg x m/s² = N
5Sample ProblemWhat is the force of a baseball weighing 0.06 kg that is accelerating towards a wall at 5,500 m/s²?m = 0.06 kga =5,500 m/s²F = ma= (0.06 kg x 5,500 m/s²) =330 N
6Newton’s Third Law of Motion Single isolated forces cannot exist!Forces always exist in pairs (action- reaction pair).“Whenever two objects interact, the force exerted on one object is equal in strength and opposite in direction to the force exerted on the other object.”
7Force of the astronaut on the satellite Force of the satellite on the astronautThe most important thing to keep in mind about action-reaction pairs is that each force acts on a different object.
8How does a nail get driven into a piece of wood by a hammer? Example 2:How does a nail get driven into a piece of wood by a hammer?Force of the nail on the hammerForce of the hammer on the nailForce of wood on nail