AIEEE 2004 (Physics) Mock Test

One mole of ideal monoatomic gas ($\gamma =5/3$) is mixed with one mole of diatomic gas ($\gamma =7/5$). What is $\gamma$ for the mixture? $\gamma$ denotes the ratio of specific heat at constant pressure to that at constant volume.

If the temperature of the sun were to increase from $T$ to $2T$ and its radius from $R$ to $2R$, then the ratio of the radiant energy received on earth to what it was previously will be:

Which of the following statements is correct for any thermodynamic system?

Two thermally insulated vessels $1$ and $2$ are filled with air at temperatures $(T_1,T_2)$, volume $(V_1,V_2)$ and pressure $(P_1,P_2)$ respectively. If the valve joining the two vessels is opened, the temperature inside the vessel at equilibrium will be:

A radiation of energy $E$ falls normally on a perfectly reflecting surface. The momentum transferred to the surface is: