This question already has an answer here:

How did we come to know that, for example, the quantity Work=Force*distance is conserved?


marked as duplicate by Conifold, Michael Weiss, Logan M Jan 18 '17 at 16:21

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

Browse other questions tagged or ask your own question.