(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Imagine some helium in a cylinder with initial volume of 1 liter and an initial pressure of 1 atm. Somehow the helium is made to expand to a final volume of 3 liters, in such a way that its pressure rises in diect proportion to its volume.

a) calculate the work done on the gas during this process , assuming that there are no "other" types of work being done.

b) Calculate the change in the helium's energy content during this process

c) calculate the amount of heat added to or removed from the helium during this process

d) Describe what you might do to cause the pressure o rise as the helium expands

2. Relevant equations

W=-integral(from V_i to V_f) P(V) dV (quasistatic)

W=-P*delta(V)

delta(U)= W+Q

delta(U)=f/2*NkT

3. The attempt at a solution

a) P=m*V+ b , where m is the slope and b is the y-int.

m=delta(P)/delta(V)= (3-1)/((3-1)=1 and b=0

P=V

W=integral (from 1 atm to 3 atm) (V dV)

b) delta(U)=f/2*NkT=(f/2)*PV

c)delta(U)=Q+W==> Q=delta(U)-W

d) some source of external heat such as a flame is probably causing the balloon to expand

Did I do everything correctly?

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# Homework Help: Compression work problem

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