An insulated box containing a diatomic gas of molar mass $M$ is moving with velocity $v$. The box is suddenly stopped. The resulting change in temperature is :-

The average translational kinetic energy of a molecule in a gas is $E_1$. The kinetic energy of the electron $(e)$ accelerated from rest through a potential difference of $V$ volts is $E_2$. The temperature at which $E_1 = E_2$ is possible is (where $N_A$ is Avogadro's number, $k_B$ is Boltzmann constant, and $R$ is the gas constant):

Molecules in the atmosphere are attracted by the gravitational force of the Earth. Explain why all of them do not fall onto the Earth,just like an apple falling from a tree.

An ideal gas $(\gamma = 1.5)$ is expanded adiabatically. To reduce the root mean square velocity of the molecules by a factor of $2$,the gas should be expanded by how many times?

$0.056 \, kg$ of Nitrogen is enclosed in a vessel at a temperature of $127 \, ^{\circ}C$. The amount of heat required to double the speed of its molecules is $k \, cal$. (Take $R = 2 \, cal \, mole^{-1} K^{-1}$)

For a diatomic gas,the change in internal energy at constant pressure and the change in internal energy for a unit temperature change are $U_1$ and $U_2$ respectively. Then $U_1 : U_2$ is equal to: