在与热现象相关的物理过程中,能的转化和守恒定律的具体表现形式就是热力学第一定律.其内容是:物体热力学能(内能)的增量ΔU等于外界对物体所做的功W加上物体从外界吸收的热量Q,表达式为:ΔU=Q+W. In the physical process related to the thermal phenomenon, the concrete manifestation of the law of transformation and conservation of energy is the first law of thermodynamics, which states that the increment ΔU of the thermodynamic energy (internal energy) of an object is equal to the work done by the outside world on the object W Coupled with objects from the outside world to absorb heat Q, the expression is: ΔU = Q + W.