Question

The given $P-U$ graph shows the variation of internal energy of an ideal gas with increase in pressure. Which of the following $P-V$ graphs is equivalent to this graph?

• A.
• B.
• C.
• D.

Answer 1

The correct option is B


We know that, internal energy,

$U=\frac{f}{2}nRT$

where $n$ is the number of moles, $f$ is the no. of degree of freedom, $R$ is the gas constant, $T$ is temperature.
$\Rightarrow U\propto T$
Hence $V$ is constant and $P$ is increasing.