STANDARD Physics Thermodynamics Class 11 Questions

"Two systems in thermal equilibrium with a third system separately are in thermal equilibrium with each other." This statement is

Internal energy of an ideal gas depends upon

Which of the following is not a path function?

An electric heater supplies heat to a system at a rate of 120 W. If system performs work at a rate of 80 J s⁻¹, the rate of increase in internal energy is

A vessel has 6 g of oxygen at pressure P and temperature 400 K. A small hole is made in it so that oxygen leaks out. How much oxygen leaks out if the final pressure is \( \frac{P}{2} \) and temperature 300 K?

An ideal gas undergoing a change of state from A to B through four different paths I, II, III and IV as shown in the P-V diagram that lead to the same change of state, then the change in internal energy is

1 kg of water is heated from 40°C to 70°C. If its volume remains constant, then the change in internal energy is (specific heat of water = 4148 J kg⁻¹ K⁻¹)

A cylinder contains 10 kg of gas at a pressure of \( 10^7 \) N m\(^{-2}\). The quantity of gas taken out of the cylinder, if final pressure is \( 2.5 \times 10^6 \) N m\(^{-2}\) is

A gas at 300 K has pressure \( 4 \times 10^{-10} \) N m\(^{-2}\). If \( k_B = 1.38 \times 10^{-23} \) J K\(^{-1}\), the number of molecules per cm\(^3\) is of the order of

The relation between the slope of isothermal curve and slope of adiabatic curve

For a gas of molecular weight M, specific heat capacity at constant pressure is γ = \( rac{C_p}{C_v} \)

When the temperature of a gas filled in a closed vessel is increased by 1°C, its pressure increases by 0.4 percent. The initial temperature of gas was

Two moles of oxygen is mixed with eight moles of helium. The effective specific heat of the mixture at constant volume is

One mole of an ideal monatomic gas at temperature \( T_0 \) expands slowly according to the law \( \frac{P}{V} = \) constant. If the final temperature is \( 2T_0 \), heat supplied to the gas is

The amount of heat supplied to \( 4 \times 10^{-2} \) kg of nitrogen at room temperature to rise its temperature by 50°C at constant pressure is (Molecular mass of nitrogen is 28 and \( R = 8.3 \text{ J mol}^{-1} \text{ K}^{-1} \))

A sample of ideal gas (γ = 1.4) is heated at constant pressure. If 100 J of heat is supplied to the gas the work done by the gas is

What amount of heat must be supplied 35 g oxygen at room temperature to raise its 80°C at constant volume? (molecular mass of oxygen is 32 and R = 8.3 J mol⁻¹ K⁻¹)

Heat is supplied to a diatomic gas at pressure. The ratio of ΔQ : ΔU : W is

A 10 kW drilling machine is used to drill a bore in a small aluminium block of mass 8 kg. Find the rise in temperature of the block in 2.5 minutes, assuming 50% power is used up in heating the machine itself or lost to the surroundings. (Specific heat of aluminium = 0.91 J g⁻¹ °C⁻¹)

The temperature of equal masses of three different liquids A, B and C are 12°C, 19°C and 28°C respectively. The temperature when A and B are mixed is 16°C and when B and C are mixed is 23°C. The temperature when A and C are mixed is

The specific heat of air at constant 0.172 Cal g⁻¹°C⁻¹. The change in internal energy when 5g of air is heated from 0°C to 4°C at constant volume is

At what temperature will the speed of sound in air be 3 times its value at 0°C?

Match the column I (type of processes) with column II (feature).

A block of ice at −8°C is slowly heated and converted to steam at 100°C. Which of the following curves represents the phenomena qualitatively?

If 10 g of ice is added to 40 g of water at 15°C, then the temperature of the mixture is (specific heat of water = 4.2 × 10³ J kg⁻¹ K⁻¹, Latent heat of fusion of ice = 3.36 × 10⁵ J kg⁻¹)

If R is universal gas constant, the amount of needed to raise the temperature of 2 moles of an ideal monatomic gas from 273 K to 373 K when no work is done is

According to equipartition law of energy each particle in a system of particles have thermal E equal to

A gas mixture consists of 2 moles of oxygen and 4 moles of argon at temperature T. Neglecting all vibrational modes, the total internal energy of the system is

The given P-V diagram shows expansion of a gas. Which one of the following statement is true?

The ratio of the molar heat capacities of a diatomic gas at constant pressure to that at constant volume is

If an ideal gas undergoes isothermal process from some initial state i to the final state f, then the change in internal energy during this process is

A pan filled with hot food cools from 94°C to 86° in 2 minutes when the room temperature is at 20°C. The time taken to cool it from 71°C to 69°C is

Two bars of same length and same cross-sectional area but of different thermal conductivities, K₁ and K₂ are joined end to end as shown in the figure. One end of the compound bar is at temperature T₁ and the opposite end at temperature T₂ (where T₁ > T₂). The temperature of the junction is

A gas is expanded from volume V₀ to 2V₀ under three different processes, as shown in the figure. Process 1 is isobaric process, process 2 is isothermal and process 3 is adiabatic. Let ΔU₁, ΔU₂ and ΔU₃ be the change in internal energy of the gas in these three processes, then

The heat capacity per mole of water is- (R is universal gas constant)

If for a gas \( \frac{R}{C_v} = 0.67 \), this gas is made up of molecules which are

The work done in adiabatic process is given by

The isothermal diagram of a gas at three different temperatures T₁, T₂ and T₃, is shown in the given figure. Then

1 mole of a gas with γ = 7/5 is mixed with 1 mole of gas with γ = 5/3, the value of γ of the resulting mixture of

A molecule of a gas has six degrees of freedom. Then the molar specific heat of the gas at constant volume is

An ideal gas system undergoes an isothermal process, then the work done during the process is

The heat absorbed by the system in going through the cyclic process as shown in figure is

When the state of a gas adiabatically changed from an equilibrium state A to another equilibrium state B, an amount of work done on the system is 35 J. If the gas is taken from state A to B via process in which the net heat absorbed by the system is 12 cal, then the net work done by the system is (1 cal = 4.19 J)

Volume versus temperature graphs for a given mass of an ideal gas are shown in figure at two different values of constant pressure. What can be inferred about relation between P₁ and P₂?

A rectangular body has maximum wavelength λₘ at 2000 K. Its corresponding wavelength at 3000 K will be

If a gas is compressed adiabatically by doing work of 150 J, the change in internal energy of the gas is

Experimental investigations show that the intensity of solar radiation is maximum for a wavelength 480 nm in the visible region. Estimate the surface temperature of sun. (Given Wien's constant b = 2.88 × 10⁻³ m K).

A cycle tyre bursts suddenly. What is the type of this process?

The wavelength of maximum intensity of radiation emitted by a star is 289.8 nm. The radiation intensity of the star is (Stefan's constant = 5.67 × 10⁻⁸ W m⁻² K⁻⁴, Wien's constant b = 2898 μm K)

A monatomic gas is compressed adiabatically to \( \frac{1}{4} \) of its original volume, the final pressure of gas in terms of initial pressure P is