Why isn energy conserved as it transfers between object in a closed system?

Answer 1

Energy is always conserved. The "why" is a bit difficult to understand; according to Noether's Theorem, this is related to the fact that the laws of physics don't change over time. But that's a lot of advanced math. But that's how conservation of energy is derived nowadays.

Answer 2

Energy is conserved in a closed system as it transfers between objects through various mechanisms (such as heat, work, or radiation). This is based on the principle of conservation of energy, which states that energy cannot be created or destroyed, only transferred or converted from one form to another. The total energy of a closed system remains constant throughout these transfers.