Physics Thermodynamics questions from JEE Main 2005.
A gaseous mixture consists of $16 \mathrm{~g}$ of helium and $16 \mathrm{~g}$ of oxygen. The ratio $\frac{C_p}{C_v}$ of the mixture is
A system goes from $A$ to $B$ via two processes I and II as shown in the figure. If $\Delta \mathrm{U}_1$ and $\Delta \mathrm{U}_2$ are the changes in internal energies in the processes I and II respectively, the 
The figure shows a system of two concentric spheres of radii $r_1$ and $r_2$ and kept at temperatures $T_1$ and $T_2$ respectively. The radial rate of flow of heat in a substance between the two concentric sphere is proportional to 
The temperature-entropy diagram of a reversible engine cycle is given in the figure. Its efficiency is 
Which of the following is incorrect regarding the first law of thermodynamics?