List of top Physics Questions on Thermodynamics asked in JEE Main

Pressure of an ideal gas, contained in a closed vessel, is increased by 0.4% when heated by $ 1^\circ \text{C} $. Its initial temperature must be :

An ideal gas exists in a state with pressure $ P_0 $, volume $ V_0 $. It is isothermally expanded to 4 times of its initial volume $ (V_0) $, then isobarically compressed to its original volume. Finally the system is heated isochorically to bring it to its initial state. The amount of heat exchanged in this process is :

Match List-I with List-II.

There are two vessels filled with an ideal gas where volume of one is double the volume of the other. The large vessel contains the gas at 8 kPa at 1000 K while the smaller vessel contains the gas at 7 kPa at 500 K. If the vessels are connected to each other by a thin tube allowing the gas to flow and the temperature of both vessels is maintained at 600 K, at steady state the pressure in the vessels will be (in kPa).

A gas is kept in a container having walls which are thermally non-conducting. Initially the gas has a volume of 800 $ cm^3 $ and temperature 27°C. The change in temperature when the gas is adiabatically compressed to 200 $ cm^3 $ is: (Take $ \gamma $ = 1.5 : $ \gamma $ is the ratio of specific heats at constant pressure and at constant volume)

A piston of mass M is hung from a massless spring whose restoring force law goes as F = -kx, where k is the spring constant of appropriate dimension. The piston separates the vertical chamber into two parts, where the bottom part is filled with 'n' moles of an ideal gas. An external work is done on the gas isothermally (at a constant temperature T) with the help of a heating filament (with negligible volume) mounted in lower part of the chamber, so that the piston goes up from a height $ L_0 $ to $ L_1 $, the total energy delivered by the filament is (Assume spring to be in its natural length before heating)

During the melting of a slab of ice at 273 K at atmospheric pressure:

An amount of ice of mass $ 10^{-3} $ kg and temperature $ -10^\circ C $ is transformed to vapor of temperature $ 110^\circ C $ by applying heat. The total amount of work required for this conversion is,
(Take, specific heat of ice = 2100 J kg$^{-1}$ K$^{-1}$,
specific heat of water = 4180 J kg$^{-1}$ K$^{-1}$,
specific heat of steam = 1920 J kg$^{-1}$ K$^{-1}$,
Latent heat of ice = $ 3.35 \times 10^5 $ J kg$^{-1}$,
Latent heat of steam = $ 2.25 \times 10^6 $ J kg$^{-1}$)

Water falls from a height of 200 m. What is the increase in temperature when it touches the bottom? (Assume that all the heat goes into the same amount of mass which was falling).

A monoatomic gas is stored in a thermally insulated container. The gas is suddenly compressed to $ \frac{1}{8} $th of its initial volume. Find the ratio of final pressure to initial pressure.

N moles of a polyatomic gas (f = 6) must be mixed with two moles of a monoatomic gas so that the mixture behaves as a diatomic gas. The value of N is :

A mixture of one mole of a monoatomic gas and one mole of a diatomic gas (rigid) are kept at room temperature ($27^\circ \text{C}$). The ratio of specific heat of gases at constant volume respectively is: