Test Index

Thermodynamics Part 2

Section: Physics

© examsnet.com

Question : 13 of 100

Marks: +1, -0

The internal energy

(U)

(p)

(V)

of an ideal gas are related as

U=3 p V+4

[26 Feb 2021 Shift 2]

diatomic only
polyatomic only
Either monoatomic or diatomic
monoatomic only

Solution:

Given, ideal gas equation,

U=3 p V+4

Here,

U=

internal energy,

p=

pressure

and

V=

volume.

By ideal gas equation,

p V=n R \Delta T

=R \Delta T

(\because n=1) \ldots (i)

\Delta U \; =n C_{v} \Delta T=3 p V+4

\; =n \frac{f}{2} R \Delta T=3 p V+4

\Rightarrow f R \Delta T \; =6 p V+8

\Rightarrow f \cdot p V \; =6 p V+8

[From Eq. (i)]

\Rightarrow f \; =6+\frac{8}{p V}

[From Eq. (i)] As, degree of freedom is more than 6 .

\therefore

Gas is polyatomic.

© examsnet.com

Go to Question:

Prev Question

Next Question