# Thermal Physics - Internal Energy

#### bon

1. Homework Statement

A gas obeys the equation p(V-b) = RT and has cv independent of temperature. Show:

(a) the internal energy is a function of temperature only
(b) the ratio cp/cv is independent of temperature and pressure
(c) the equation of an adiabatic change has the form p(V-b)^gamma = const (where gamma = cp/cv )

2. Homework Equations

3. The Attempt at a Solution

Not sure where to go for this one...

I know that for an ideal gas U = 3/2 n R T

But what can I use here? Where do i start? ( can i use dU = TdS - pdV? That holds for all gases, right?)

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