The system is expanded from equilibrium state a to equilibrium state b in the process of I, absorbing 500J of heat, working externally 400J; Then it is compressed to the original state a in the process of II, releasing heat 300J outward. Then, in the process of II, the change of the internal energy is[img=178x135]17e0b762b3b1660.png[/img]
A: -100J
B: 100J
C: 200J
D: -200J
A: -100J
B: 100J
C: 200J
D: -200J
举一反三
- When a system moves from A state along path I to B state, it releases heat of 100 J and obtains 50 J work at the same time; when the system does 80J work from A state along path Ⅱ to B state, then Q is（ ） A: 70J B: 30J C: －30J D: －70J
- DU = 100 J is for a system that gives off 100 J of heat and ( ) A: does no work B: does 200 J of work C: has 100 J of work done on it D: has 200 J of work done on it.
- 成人双相波除颤能量首选（ ） A: 100J B: 200J C: 300J D: 360J E: 400 J
- 小儿体外电除颤电能选择（）。 A: B: 5～20J C: D: 200～400J E: F: 10～50J G: H: 20～200J I: J: 100～200J
- Equilibrium is the condition of a system when neither its state of motion nor its internal energy state tends to change with time. A: 正确 B: 错误