1. Apr 6, 2007

### Gyroscope

1. The problem statement, all variables and given/known data
3.14
(0.5) How is the fractional change in temperature related to $$\frac{dT}{T}$$ the fractional change in pressure $$\frac{dP}{P}$$ ?
(IPhO 2006)

2. Relevant equations

$$PV^{\gamma}=\rm constant$$

3. The attempt at a solution

nC_vdT=-PdV (1), dV/dP=-nRT/(P^2)

If I substitute dV in the equation (1) it does not give the right result.

Can someone help me, please? :tongue2:

Thanks my dear friends.

2. Apr 6, 2007

### marcusl

It appears you are talking about an ideal gas? Then in
$$P=nRT/V$$
we see right away that P changes the same way as T. This is shown mathematically as

$$\frac{dP}{dT}=\frac{nR}{V},$$

$$\frac{dP}{P}=\frac{nRdT}{PV}=\frac{dT}{T}.$$

3. Apr 6, 2007

### Gyroscope

Thanks marcusl for your help. But you are wrong. :( I already solved it. Thanks anyway my dear friend.

4. Apr 6, 2007