context: The first law of thermodynamics asserts that energy (but not necessarily thermodynamic free energy) is always conserved and that heat flow is a form of energy transfer. For homogeneous systems, with a well-defined temperature and pressure, a commonly used corollary of the first law is that, for a system subject only to pressure forces and heat transfer (e.g., a cylinder-full of gas) without chemical changes, the differential change in the internal energy of the system (with a gain in energy signified by a positive quantity) is given as
question: శక్తి ఎల్లప్పుడూ పరిరక్షించబడుతుంది మరియు వేడి ప్రవాహం శక్తి బదిలీ యొక్క ఒక రూపం.
answers: first law of thermodynamics