The overcoming of a resisting force over a distance. The work performed when a force F overcomes an equal resisting force along a distance s in the same direction equals Fs, i.e., F times s.
If the force is not in the direction of the motion, only the vector component of F in that direction enters the calculation. Thus, If a force F acts on a body and the body moves a distance s at an angle θ to the line of action of the force then the work done W is defined as being the product of the force, distance, and the cosine of the angle, i.e.,
The unit of work, or energy transfer, is the joule (J). One joule is the energy transferred when a force of 1 newton is applied over a distance of 1 meter in the direction of the force. This makes the joule the equivalent of kg m2 s-2 with dimensions of [M]1 [L]2 [T]-2.
Energy can be defined as the ability to perform work.
Related category CLASSICAL MECHANICS
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