why physics says that a work is only done when the applied force makes a object or body move
Answers
Physics formula for Work is
Force × Displacement
Even if a huge amount of force is acting on a body and no displacement is produced then the Overall work done on the body by the force is zero cause here displacement is zero.
Work = Force× Displacement
Work = F × 0 = 0
For example:-
A weight lifter who is carring some weight and not moving is considered as a situation of no work done. Cause even if he is applying force still there is no displacement caused. So, the work done is zero. Although the weight lifter gets tired cause of the stretching of muscles.
In the language of physics you can't just sit on your couch whole day and call it a "day" and get tired already(I do though xD). You have to bring some displacement out of the force you are applying on the body.
Cheers!
Answer:
Because if a body doesn't move it will stay at the same place. Think that the applied force is invisible and the object is at a black vacant place and you are the observer. Then if the body doesn't move you can't find any thing else happening with the body. It means that no work is occurring. It means that displacement is the signal of a work happening.
hope you will like my answer and agree with me.