system and surrounding

[Maryam Alturki]

how do we identify a system and the surrounding in a problem? also why are we not focusing on surroundings as much as we are systems?

[Caroline Wight 3B]

The system is the region of interest. The surroundings are everything else(we usually calculate to find the immediate surrounds). We focus on the system because it is the area we are interested in the most. Ideally, Qsystem+Qsurroundings=0 so you could use that if you want to solve for the surroundings.

[Maryam Alturki]

The system is the region of interest. The surroundings are everything else(we usually calculate to find the immediate surrounds). We focus on the system because it is the area we are interested in the most. Ideally, Qsystem+Qsurroundings=0 so you could use that if you want to solve for the surroundings.

Okay so I get this now, thank you. But how do we apply this to a question? I haven't looked over any of the textbook problems yet but how would this be in terms of solving a problem?

[305568482]

Hi Maryam, a system would be something like a box and everything in it and the surrounding would be everything outside of it. I watched a video which explained that when work is done on the system then w is positive and if it is done by the system then w is negative.

[Emily Lee 2H]

+Q=heat transferred into the system
-Q=heat transferred out of the system
+W=work being done on the system
-W=work being done by the system

[Jasmine Catalan 1H]

Hi, so we mainly focus on the system because that is our main interest, to see how it acts. However if you want to calculate surrounding the Qsystem+Qsurroundings=0. If you know one you can get the other through this equation.

[Natalie Hurd 1H]

A system is the object of interest and the surrounding is everything else.

[Morganne Malloy 1l]

Also, one way to think about it is that the system is a drop of water and the environment is the ocean. They mix when you drop the drop into the ocean and then see how the ocean reacts, which isn't much cause the ocean is so big.