$A$ gas at normal temperature is suddenly compressed to one-fourth of its original volume. If $\gamma = 1.5$, then the increase in the temperature of the gas in Kelvin is ($\gamma$ is the ratio of specific heats).

$A$ sample of an ideal gas is contained in a cylinder. The volume of the gas is suddenly decreased. $A$ student makes the following statements to explain the change in pressure of the gas:
$I.$ The average kinetic energy of the gas atoms increases.
$II.$ The atoms of the gas hit the walls of the cylinder more frequently.
$III.$ Temperature of the gas remains unchanged.
Which of these statements is true?

During an adiabatic expansion of $2\, moles$ of a gas,the change in internal energy was found to be $-50\, J$. The work done during the process is ...... $J$.

$A$ diesel engine has a compression ratio of $20:1$. If the initial pressure is $1 \times 10^5 \ Pa$ and the initial volume of the cylinder is $1 \times 10^{-3} \ m^3$, then how much work does the gas do during the compression (in $J$)? (Assume the process as adiabatic) $(C_V=20.8 \ J/mol \ K, \gamma=1.4, (20)^{1.4}=66.3)$

An ideal gas at $27 \, ^\circ C$ is compressed adiabatically such that its volume becomes $8/27$ of its original volume. If $\gamma = 5/3$ for the gas,the increase in temperature of the gas is ..... $K$.

One mole of helium is adiabatically expanded from its initial state $({P_i}, {V_i}, {T_i})$ to its final state $({P_f}, {V_f}, {T_f})$. The decrease in the internal energy associated with this expansion is equal to