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1 st Law of Thermodynamics. More Problems. In the equation Q= U+W , the quantities Q and W represent The heat released by the system and the work done by the system. The heat released by the system and the work done on the system.
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1st Law of Thermodynamics More Problems
In the equation Q=U+W, the quantities Q and W represent • The heat released by the system and the work done by the system. • The heat released by the system and the work done on the system. • The heat supplied to the system and the work done by the system. • The heat supplied to the system and the work done on the system.
25 kJ of work is done on the system consisting of 3 kg of water by stirring it with a paddle wheel. During this time, 62.7 kJ of heat is removed. What is the change in internal energy of the system? • -87.7 kJ • -37.7 kJ • +37.7 kJ • +87.7 kJ
300 J of work is done on the gas during compression. In the process, 400 J of energy leaves the gas by heat. What is the change in the internal energy of the gas? • -700 J • -100 J • +100 J • +700 J
A thermodynamic system undergoes a process in which its internal energy decreases by 500 J. At the same time, 220 J of work is done on the system. Find the heat involved in the process. • -720 J • -280 J • +280 J • +720 J
If 400 kJ is added to a gas that expands and does 800 kJ of work, what is the change in the internal energy of the gas? • -1200 kJ • -400 kJ • +400 kJ • +1200 kJ
A diatomic gas does 300 J of work and also absorbs 600 J of heat. What is the change in the internal energy of the gas? • -900 J • -300 J • +300 J • +900 J
Consider that 200 J of work is done on a system and 70 J of heat is extracted from the system as heat. What is the change in internal energy of the system? • -270 J • -130 J • +130 J • +270 J
When 20 J of heat is absorbed by a gas, the system performs 30 J of work. What is the change in the internal energy of the gas? • -50 J • -10 J • +10 J • +50 J
During a certain thermodynamic process, a sample of gas expands and cools, reducing its internal energy by 3000 J. During which 500 J of heat is added. How much work is done during this process? • -3500 J • -2500 J • +2500 J • +3500 J
While a gas does 200 J of work, its internal energy increases by 700 J. How much heat is involved in the process? • -900 J • -500 J • +500 J • +900 J