Question

The ratio of two specific heats of gas $ {{C}_{p}}/{{C}_{V}} $ for argon is 1.6 and for hydrogen is 1.4. If adiabatic elasticity of argon at pressure p is E, then at what pressure the adiabatic elasticity of hydrogen will also be equal to E?

• A. p
• B. 1.4 p
• C. $ \frac{7}{8}p $
• D. $ \frac{8}{7}p $

Answer 1

Answer: (D)

Adiabatic elasticity $ E=\gamma p, $
For argon, $ {{E}_{Ar}}=1.6\,p $ ...(i)
For hydrogen, $ {{E}_{H}}=1.4\,p $ ...(ii)
As elasticity of argon and hydrogen are equal
$ \therefore $ $ 1.6p=1.4\,p $
or $ p=\frac{1.6}{1.4}=\frac{8}{7}p $