
Newtons second law explains whathappens to an object when an unbalancedforce acts on it. Newtons Second Law of Motion An unbalanced force acting on an objectaffects the motion of an object by causingthat objects velocity to change.The object accelerates. Law of Inertia: Crash Tests What forces act on the crash-test dummyto slow its forward motion?Seatbelt: the seatbelt tightensimmediately to slow down the dummyand to absorb energy.Inflating air bag: the bag exerts a forcethat slows down the dummys forwardmotion, absorbing its energy andprevents it from hitting the steeringwheel. Think about being in a moving carthat is involved in a front-end collision.The collision makes the car stop suddenlybut what happens to you, the passenger? Because you have inertia, you continuemoving forward. Newtons First Law of Motion Often called the Law of Inertia.Inertia is the tendency of an object toresist a change in its motion. Thus, unless an unbalanced force acts, anobject at rest remains at rest, and anobject in motion remains in motion withthe same speed and direction. Newtons First Law of Motion Newtons first law of motion states thatthe motion of an object does not changeas long as the net force acting on theobject is zero.

Published his worksafter many years in abook entitles Principia. Sir Isaac Newton Newton built on thework of scientists suchas Galileo.

Newtons Laws of MotionPhysical Science9th GradeDesigned to demonstrate each law andencourage students to see their applicationĢ.
