Question

One $kg$ of a diatomic gas is at a pressure of $8\times {10}^{4}N/m^2$. The density of the gas is $4$ $kg/m^3$. What is the energy of the gas due to its thermal motion ?

• A. $3\times {10}^{4}J$
• B. $5\times {10}^{4}J$
• C. $6\times {10}^{4}J$
• D. $7\times {10}^{4}J$

Answer 1

Answer: (B)

$5\times {10}^{4}J$

$E=\frac{5}{2}nRT$
$=\frac{5}{2}$ PV
$=\frac{5}{2}P\frac{m}{P}$
$=\frac{5}{2}\times \frac{(8\times {10}^4)\left(1\right)}{4}=5\times {10}^{4}J$