The magnitude of the force acting on a body due to gravity. It is generally assumed that when a body of mass m is near the Earth’s surface it is acted upon by a uniform gravitational force equal to −mgk, where k is a unit vector directed vertically upwards and g is the magnitude of the acceleration due to gravity. Thus, the weight of the body equals mg. Weight has dimensions MLT−2, the same as force, and the SI unit of weight is the newton.