List of top Physics Questions on Laws of thermodynamics asked in MHT CET

An ideal gas having pressure P, volume V and temperature T undergoes a thermodynamic process in which \(dW=0\) and \(dQ\lt 0\). Then, for the gas
Heat is supplied to a rigid diatomic gas at constant pressure. The ratio of \(\Delta Q:\Delta U:\Delta W\) is \(\{\Delta Q=\text{heat supplied},\Delta U=\text{change in internal energy},\Delta W=\text{work done during expansion}\}\)
When the temperature of 4 moles of a gas was increased from \(70^{\circ }\)C to \(90^{\circ }\)C, at constant volume, the change in internal energy was \(60\text{ J}\). The total heat capacity of the gas at constant volume is
Two moles of a rigid diatomic gas does a work \(\frac{Q}{4}\) when the amount of heat supplied is \(Q\). In this process the total heat capacity of the gas is (\(R\) = gas constant)
We consider a thermodynamic system. If \(\Delta U\) is the increase in internal energy and \(W\) is the work done by the system, which one of the following statement is true?
One mole of an ideal diatomic gas undergoes a transition from A to B along a path AB as shown. The change in internal energy of the gas during the transition is
If the ratio of molar heat capacities \(\frac{C_{p}}{C_{v}}=\gamma\) then the ratio of \(\frac{\Delta Q}{\Delta U}\) and \(\frac{\Delta Q}{\Delta W}\) in an isobaric process is
\(1\) g of water of volume \(1\text{cm}^{3}\) at \(100^{\circ }\text{C}\) is converted into steam of same temperature under normal atmospheric pressure (\(10^{5}\) Pa). The volume of steam formed equals \(1671\text{cm}^{3}\). If the latent heat of vaporisation of water is \(2256\) J/g, the change in internal energy is
Six moles of oxygen gas is heated from \(20^{\circ }\)C to \(35^{\circ }\)C at constant volume. If specific heat capacity at constant pressure is \(8\text{ cal mol}^{-1}\text{k}^{-1}\) and gas constant is \(2\text{ cal mol}^{-1}\text{k}^{-1}\). The change in internal energy of the gas is
An ideal mono-atomic gas is heated at constant pressure. The fraction of the total energy applied which increases the internal energy for the gas is
The second law of thermodynamics deals with the transfer of
a. only work.
b. momentum.
c. heat.
d. only pressure.
For a cyclic thermodynamic process
A gas at normal temperature is suddenly compressed to one-fourth of its original volume. If \(γ = 1.5\), then the increase in the temperature of the gas in Kelvin is (\(γ\) is the ratio of specific heats)
A thermodynamic system is compressed adiabatically, then its temperature
An ideal gas at \(27^{\circ}\)C is compressed adiabatically to \((\frac{8}{27})\) of its original volume. If \(γ = 5/3\), then the rise in temperature of a gas is
A monoatomic gas at pressure P having volume V expands isothermally to a volume 3V and then adiabatically to a volume 81 V. The final pressure of the gas is (\(γ = 5/3\)).
In a cyclic process, work done by the system is
If \(\Delta Q\) is the amount of heat supplied to 'n' moles of a rigid diatomic gas at constant pressure, \(\Delta U\) is the change in internal energy and \(\Delta W\) is the work done then \(\Delta W:\Delta U:\Delta Q\) is

Two cylinders A and B fitted with piston contain equal amount of an ideal diatomic gas at temperature T K. The piston of cylinder A is free to move while that of cylinder \(B\) is held fixed. The same amount of heat is given to the gas in each cylinder. If the rise of temperature of the gas in A is \(\mathrm{dT}_{\mathrm{A}}\), then the rise in temperature of the gas in B is \(\left(\gamma=\frac{C_p}{C_v}\right)\)

Heat is given to an ideal gas in an isothermal process. Then

A. internal energy of the gas will decrease.

B. internal energy of the gas will increase.

C. internal energy of the gas will not change.

D. the gas will do negative work.

A Carnot engine has efficiency \(\frac{1}{6}\). It becomes \(\frac{1}{3}\), when the temperature of \(\operatorname{sink}\) is lowered by

57 K . The temperature of the source is

During the isothermal expansion, a confined ideal gas does \((-150) \mathrm{J}\) of work against its surroundings. This means that

A polyatomic gas is compressed to \(\left(\frac{1}{8}\right)^{\text {th }}\) of its volume adiabatically. If its initial pressure is \(\mathrm{P}_0\), its new pressure will be [Given, \(\frac{\mathrm{C}_{\mathrm{p}}}{\mathrm{C}_{\mathrm{v}}}=\frac{4}{3}\) ]

Two cylinders A and B fitted with pistons contain equal amount of an ideal rigid diatomic gas at 303 K . The piston of cylinder \(A\) is free to move and that of cylinder B is held fixed. The same amount heat is given to the gas in each cylinder. If the rise in temperature of the gas in cylinder B is 49 K , then the rise in temperature of the gas in \(A\) is

The change in the internal energy of the mass of gas, when the volume changes from V to 2 V at constant pressure P is \(\left(\gamma=\frac{\mathrm{Cp}}{\mathrm{Cv}}\right)\)