A gas at N.T.P. is suddenly compressed to $$\left(\frac{1}{4}\right)^{\text {th }}$$ of its original volume. The final pressure in (Given $$\gamma=$$ ratio of sp. heats $$=\frac{3}{2}$$ ) atmosphere is ( $$\mathrm{P}=$$ original pressure)

In a thermodynamic process, there is no exchange of heat between the system and surroundings. Then the thermodynamic process is

According to kinetic theory of gases, which one of the following statements is wrong?

What is the ratio of the velocity of sound in hydrogen $$\left(\gamma=\frac{7}{5}\right)$$ to that in helium $$\left(\gamma=\frac{5}{3}\right)$$ at the same temperature? (Molecular weight of hydrogen and helium is 2 and 4 respectively.)