JEE Mains · Physics · STD 11 - Kinetic theory of gases
- JEE Mains 2025
- Easy
- Numerical
The internal energy of air in \(4 \mathrm{~m} \times 4 \mathrm{~m} \times 3 \mathrm{~m}\) sized room at 1 atmospheric pressure will be _______ \(\times 10^6 \mathrm{~J}\). (Consider air as diatomic molecule)
Pick an option to check your answer.
Answer & Solution
Correct Answer
(B) 12
Step-by-step Solution
Detailed explanation
To find the internal energy of gas in the room.
\(\begin{aligned}
& \mathrm{U}=\mathrm{nC}_{\mathrm{v}} \mathrm{~T}=\mathrm{n} \frac{5 \mathrm{RT}}{2} \\
& =\frac{5}{2} \mathrm{PV}=\frac{5}{2} \times 10^5 \times 48=12 \times 10^6 \mathrm{~J}
\end{aligned}\)
\(\begin{aligned}
& \mathrm{U}=\mathrm{nC}_{\mathrm{v}} \mathrm{~T}=\mathrm{n} \frac{5 \mathrm{RT}}{2} \\
& =\frac{5}{2} \mathrm{PV}=\frac{5}{2} \times 10^5 \times 48=12 \times 10^6 \mathrm{~J}
\end{aligned}\)
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