21. The "'first law of thermodynamics "'is a version of the law of conservation of energy, adapted for thermodynamic systems. 22. Energy input and output will always balance according to the First Law of Thermodynamics or the energy conservation principle. 23. This is the conservation of mass-energy ( first law of thermodynamics ) contained within a part of the universe. 24. Water fuelled cars simply cannot work because of the first law of thermodynamics . . . jeez-what a boring answer! 25. In the case of energy, the statement of the conservation of energy is known as the first law of thermodynamics . 26. :: : The mirror would violate conservation of energy ( unless it had a power supply ), the first law of thermodynamics . 27. Given that a phase change is an internally reversible process, and that our system is closed, the first law of thermodynamics holds 28. This statement came to be known as the mechanical equivalent of heat and was a precursory form of the first law of thermodynamics . 29. I'd like to add that the first law of thermodynamics implies that even if we manufacture synthetic fuel ( as e . g. 30. To obtain \ lambda _ 2, we differentiate S with respect to the average energy U and apply the first law of thermodynamics :
