n moles of a gas filled in a container at temperature T is in thermodynamic equilibrium initially.  If the gas is compressed slowly and isothermally to half its initial volume the work done by the atmosphere on the piston is:

In a process the pressure of an ideal gas is proportional to square of the volume of the gas. If the temperature of the gas increases in this process, then work done by this gas:

A vessel contains an ideal monoatomic gas which expands at constant pressure, when heat Q is given to it. Then the work done in expansion is:

5 moles of Nitrogen gas is enclosed in an adiabatic cylindrical vessel. The piston itself is a rigid light cylindrical container containing 3 moles of Helium gas. There is a heater which gives out a power 100 cal/sec to the nitrogen gas. A power of 30 cal /sec is transferred to Helium through the bottom surface of the piston. The rate of increment of temperature of the nitrogen gas assuming that the piston moves slowly:

The gas law PV/2 =constant for a given amount of a gas is true for :

All the rods have same conductance ‘K’ and same area of cross section S. If  ends A and C are maintained at temperature 2T₀ and T₀ respectively then which of the following is/are correct:

A hollow copper sphere and a hollow copper cube, of same surface area and negligible thickness, are filled with warm water of same temperature and placed in an enclosure of constant temperature, a few degrees below that of the bodies. Then in the beginning :

The colour of a star indicates its :

Two identical solid spheres have the same temperature. One of the sphere is cut into two identical pieces. The intact sphere radiates an energy Q during a given small time interval. During the same interval, the two hemispheres radiate a total energy Q'. The ratio Q'/Q is equal to :

A calorimeter contains 50 g of water at 50°C. The temperature falls to 45°C in 10 minutes. When the calorimeter contains 100 g of water at 50°C, it takes 18 minutes for the temperature to become 45°C. then  the water equivalent of the calorimeter is :