Question

The pressure of a gas is equal to

• A. the total translation kinetic energy of all the molecules in unit volume
• B. the total kinetic energy of all the molecules in unit volume
• C. two thirds of the total translational kinetic energy of all the molecules in unit volume
• D. two-thirds of the total kinetic energy of all the molecules in unit volume

Answer 1

Answer: (C)

$P=\frac{m N \bar{c}^{2}}{3 V}=\frac{2}{3} \cdot \frac{1}{2} \frac{M \bar{c}^{2}}{V}=\frac{2}{3}\left(\frac{1}{2} \rho \bar{c}^{2}\right)$
or $P=\frac{2}{3} E$