Arm and leg weakness can be caused by a variety of different conditions, some of them temporary and others chronic. Excessive exercise is one cause of temporary fatigue in the major muscle groups, although this is not considered true muscle weakness.
Mass is an intrinsic property of the body and gravity is the force exerted on any body by the things that surround it. Weight, on the other hâ¦and, depends on gravity. It is equal to the product of the mass of the body and the gravitational force acting on it.
In physical science, mass refers to the degree of acceleration a body acquires when subject to a force: bodies with greater mass are accelerated less by the same force. One says the body of greater mass has greater inertia.