Compare work done ON the gas for: (i) isothermal compression from V₁ to V₂; (ii) adiabatic compression from V₁ to the SAME V₂. Which requires MORE work?
A.
The answer depends on γ of the gas
B.
Adiabatic compression requires MORE work on the gas — because gas also heats up, increasing pressure, requiring more force to compress
B. Adiabatic compression requires MORE work on the gas — because gas also heats up, increasing pressure, requiring more force to compress
14.
For isothermal compression, P-V curve is a rectangular hyperbola (PV = constant). For adiabatic compression, the P-V curve is steeper because:
A.
Temperature decreases during adiabatic compression
B.
Temperature increases during adiabatic compression — gas pressure rises faster (PV^γ = const, γ > 1) giving a steeper curve than the isotherm (PV = const)
B. Temperature increases during adiabatic compression — gas pressure rises faster (PV^γ = const, γ > 1) giving a steeper curve than the isotherm (PV = const)
15.
For adiabatic compression of an ideal gas from (P₁, V₁, T₁) to (P₂, V₂, T₂), the work done BY the gas is:
A.
W = nR(T₁ − T₂)/(γ − 1) — negative for compression since T₂ > T₁
A. W = nR(T₁ − T₂)/(γ − 1) — negative for compression since T₂ > T₁
16.
In adiabatic compression, PV^γ = constant. If a gas (γ = 7/5) is compressed to half its volume (V₂ = V₁/2), the ratio of final to initial pressure P₂/P₁ is: (NCERT Exercise 11.4 context)
For adiabatic compression with TV^(γ−1) = constant: hydrogen (γ = 7/5) is compressed adiabatically to half its volume from T₁ = 300 K. The final temperature T₂ is approximately:
