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First Law of Thermodynamics

  • Thread starter Sixty3
  • Start date
13
0
1. Homework Statement
I am looking into the first law of thermodynamics.
But I'm not sure with some parts.


2. Homework Equations
dU=Q-W What does it mean when U Q and W are negatives.
Also solids with W=0


3. The Attempt at a Solution
So the equation will change to -U=-Q+W
Does it lose it's internal energy?
 
Last edited:
1,889
192
It's

[tex] dU = \delta Q - \delta W [/tex]

If dU is negative that means that the system loses internal energy. The temperature goes down, or water freezing etc.

if [itex] \delta Q [/itex] is negative, the system supplies heat to its surroundings.

if [itex] \delta W [/itex] is negative, the system does negative work on its surroundings, this is the same as positive work done on the system
 

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