Question

What is the law of conservation of energy??​

Answer 1

According to this law:-

Energy is neither be created nor be destroyed ...its just changes its forms

Answer 2

the law of conservation of energy states that energy cannot be created nor be destroyed and is energy is always conserved but it can change from one form to another .
taking the example of a ball thrown from a height .. so
taking the example of a ball thrown from height its kinetic energy increases while the potential energy decreases so to conserve its energy and when it hits ground it its kinetic energy is transformed into sound energy and heat energy ( that is actually very less) .