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troytroy
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Homework Statement
When 120J of heat are added to this gas, the temperature of the gas changes. Find the change in temperature if the heat is added at (a) constant volume. (b) constant pressure.
Homework Equations
The equation of state of at the gas is (p + 50)V = 10T
The internal energy of this gas is given by U = 20T + 50V + 40
The Attempt at a Solution
For part (a) I used the fact that U = W + Q, but since the volume is constant I know that U=Q=120J. From this I substitute V for the equations to obtain an equation for T with pressure as the independent variable. T = (4p + 200)/(75 + p) then dT/dp = 100/(75+p)^2. Is this the right way to go about this problem? or should I use something like since U = Q and the differential of U(T,V) is
dU = (partial dU/dT)DT + (partial dU/dV)DV and then take the partial of U with respect to T, which would be dU = 20 dT. THEN 20 dT = 120J since U = Q. Thus, dT = 6. I am not sure which route to go. Similar question for part (b). Thanks for any advice!