Work is Change in Energy
The work done on or by an system is defined as the transfer of energy into or out of the system as a result of the application of a force external to the system.
Thus, the work done on or by a system is equal to the change in energy of the system. In addition, in order to change the energy of an object (or of a system), work must be done on or by the object (or system) resulting from the application of a force external to the system. |
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