Question

Why is there a focus on conserving energy resources if the Law of Conservation of Energy states that the amount of energy in a system (i.e. the Universe) remains constant over time?

A.) Only Physics students know about the Law of Conservation of Energy.

B.) Earth is losing its energy to space and cannot recapture it.

C.) The total amount of energy remains constant, but some energy is lost to forms that cannot be used for mechanical work every time energy is transformed.

D.) Energy used to perform work cannot be recovered into a useful form.

Answer 1

(C) is the best choice. Energy of the universe remain conserved, no matter energy converted into other form. If we compress a spring then our biological energy converted into mechanical energy(elastic potential energy)in spring which can further used to do some useful during elongation of spring . But entire energy supplied by us to spring is not converted into elastic potential energy some part of energy is lost in friction in the form of heat if repeat the process, that can't be recover .