See Also: Newton's laws of motion(encyclopedia)
Low Newton, Newton Haven Beach(tourism)
Newton(medicine)
newton(encyclopedia)
Newton(dictionary)
Newton's law(medicine)
Newton, Sir Isaac(medicine)
Newton's disk(medicine)
Newton's law of gravitation(encyclopedia)
Newton, Sir Isaac(encyclopedia)

Newton's laws of motion (sh)




Relations between the forces acting on a body and the motion of the body, formulated by Isaac Newton.

The laws describe only the motion of a body as a whole and are valid only for motions relative to a reference frame. Usually, the reference frame is the Earth. The first law, also called the law of inertia, states that if a body is at rest or moving at constant speed in a straight line, it will continue to do so unless it is acted upon by a force. The second law states that the force F acting on a body is equal to the mass m of the body times its acceleration a, or F = ma. The third law, also called the action-reaction law, states that the actions of two bodies on each other are always equal in magnitude and opposite in direction.