From early grades we study energy is the ability to do work by a body or an agent. When an agent does work by applying force, it is said that amount of energy equal to work will be transferred to the body on which work is done. Whenever work is done transfer of energy takes place. The body which supplies energy is considered as agent who is doing work and its work is taken positive and another body on which work is done gains energy and the its work is taken negative.
Calculation of Work: By the fundamental method studied in early grades we calculate work by product
of force and displacement of point of application of force.
See this video on work and its calculation – https://youtu.be/WEriI0hK0lc
Sometimes applied force varies with position of body then to understand how to calculate work by a
variable force see this video – https://youtu.be/5fenCV_tUHw
Always remember that no matter how logical and advance the problem is, we will use always the
fundamental way to calculate the work.
Many times students feel for advance problem there are some
advanced ways for work calculations. In further study we will see some more cases but the fundamental
method explained above will always be applicable.
See below examples on work calculations –