Question

In the following V - T diagram what is the relation between $P_1$ and $P_2$ :

• A. $P_2=P_1$
• B. $P_2>P_1$
• C. $P_2<P_1$
• D. can not be predicted

Answer 1

Answer: (C)

$P_2<P_1$

From ideal gas equation,
$PV=RT$ where
P: Pressure
V: Volume
T: Temp
R: universal gas constant
$\therefore \frac{V}{T}=\frac{R}{P}$
In the V-T graph, slope of 2 is greater than slope of 1.
$\frac{V_2}{T_2}$ > $\frac{V_1}{T_1}$
$\Rightarrow \frac{1}{P_2}$ > $\frac{1}{P_1}$
$\Rightarrow P_2<P_1$