A: An isolated system
B: A closed system but heat and work can cross the boundary
C: A specific amount of mass in space
D: A fixed region in space where mass, heat and work can cross the boundary of that region
举一反三
- The control volume is（ ） A: A system of a certain mass B: Space body with changed position and shape C: Fixed space body D: Space body with constant shape and moving position
- We can raise the temperature of a system by adding heat, but we can’t raise its temperature by doing work on it.
- In a constant volume process for a closed system, the internal energy change of the system depends on the heat exchanged.
- Which of the following descriptions is correct? A: The microscopic viewpoint studies the large-scale properties of matter (temperature, pressure, volume, etc.). B: The part of the universe under study in thermodynamics is called the system; the parts of the universe that can interact with the system are called surroundings. C: For an open system, only matter can be transferred between system and surroundings. D: A closed system must be an isolated system, but an isolated system may not be a closed system.
- Work is taken negative when the work is done by the system and heat is taken as positive when it is transferred into the system. （ ）
内容
- 0
In a constant pressure process for a closed system, the enthalpy change of the system depends on the heat exchanged.
- 1
In a constant pressure process for a closed system, the internal energy change of the system is equal to the sum of the heat exchanged and the work.
- 2
Put left hand behind the organ or mass palpating, and push the examination region to the right-hand direction. Not only can make organ or mass fixed but also closer to the surface to ease right hand palpation. A: Deep sliding palpation B: Ballottement C: Pressure deep palpation D: Bimanual palpation
- 3
Personal space is the invisible boundary around ourselves.
- 4
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.