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George3
Sep1-09, 06:35 PM
1. The problem statement, all variables and given/known data

P = RT/(V-b) - a/V^2

Ive been trying to solve this for V and just cant get it.

2. Relevant equations


3. The attempt at a solution
IVe gotten to:
RTV^2 -aV+ab = P(V^3-V^2b)
Any Ideas?

berkeman
Sep1-09, 06:44 PM
1. The problem statement, all variables and given/known data

P = RT/(V-b) - a/V^2

Ive been trying to solve this for V and just cant get it.

2. Relevant equations


3. The attempt at a solution
IVe gotten to:
RTV^2 -aV+ab = P(V^3-V^2b)
Any Ideas?

Could you use more parenthesis to make the equation clearer? Or is its form just as written:

P = \frac{RT}{V-b} - \frac{a}{V^2}

berkeman
Sep1-09, 06:47 PM
From your partial solution, it does look like that was the original form. Collect terms and factor for V would be the next steps...

()V^3 + ()V^2 + ()V + () = 0