Question:medium
A gas for which \(\gamma =5/3\ (\gamma =C_{p}/C_{v})\) is heated at constant pressure. The percentage of heat supplied used for external work is
A gas for which \(\gamma =5/3\ (\gamma =C_{p}/C_{v})\) is heated at constant pressure. The percentage of heat supplied used for external work is
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The fraction of heat converted into work at constant pressure is R divided by Cp, which equals (gamma - 1) over gamma.
Updated On: Nov 12, 2026
- \(20\ \%\)
- \(40\ \%\)
- \(60\ \%\)
- \(80\ \%\)
Show Solution
The Correct Option is B
Solution and Explanation
Step 1: Formula-first approach
$\dfrac{W}{Q}=\dfrac{\gamma-1}{\gamma}$.
Step 2: Compute
$\dfrac{5/3-1}{5/3}=\dfrac{2/3}{5/3}=\dfrac{2}{5}$.
Step 3: Compare the options
$40\%$ matches; the other $60\%$ raises the internal energy.
Final Answer:
The fraction used for work is 40 percent. \[ \boxed{\text{(B) }40\ \%} \]
$\dfrac{W}{Q}=\dfrac{\gamma-1}{\gamma}$.
Step 2: Compute
$\dfrac{5/3-1}{5/3}=\dfrac{2/3}{5/3}=\dfrac{2}{5}$.
Step 3: Compare the options
$40\%$ matches; the other $60\%$ raises the internal energy.
Final Answer:
The fraction used for work is 40 percent. \[ \boxed{\text{(B) }40\ \%} \]
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