7-1 Internal Energy Heat&work内能 功热量 1. Two basic concepts(系统与外界): Thermodynamic system: a system that can interact with its surroundings in at least two ways one of which must be heat transfer §而3e成能e功s超毒 Thermodynamic system its surroundingsits surroundings 1. Two basic concepts(系统与外界）: is a system that can interact with its surroundings in at least two ways, one of which must be heat transfer. Thermodynamic system: The surroundings : are everything outside the system. Thermodynamic system §7-1 Internal Energy Heat &Work 内能 功 热量 §7-1 Internal Energy Heat &Work 内能 功 热量