Question

what do we mean by constants of motion & what do we mean by conservation laws?

Answer 1

do u have a question? conservation laws may refer to forces or energy. For instance gravity is a conservational forces unlike friction because it is taking energy away from the system.

Answer 2

conservation laws are those that state the starting total energy must be equal to the ending total energy, thermodynamics says that energy cannot be created or destroyed there is always the same overall amount, momentum describes the mass times velocity of a group of objects which is always conservated, except for a part that is always wasted as heat, but that heat along with the momentum will always sum the same.