NEET Physics Thermodynamics Class 11 Questions

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

The pressure of a gas changes linearly with volume from A to B as shown in figure. If no heat is supplied to or extracted from the gas then change in the internal energy of the gas will be

The power radiated by a black body is P and it radiates maximum energy at wavelength \( \lambda_0 \). If the temperature of the black body is now changed so that it radiates maximum energy at wavelength \( 3\lambda_0 \), the power radiated by it becomes nP. The value of n is:

Which one of the following is \( \nu_m - T \) graph for perfectly black body? \( \nu_m \) is the frequency of radiation with maximum intensity. T is the absolute temperature.

The value of \( \gamma = \frac{C_p}{C_v} \), for hydrogen, helium and another ideal diatomic gas X (whose molecules are not rigid but have an additional vibrational mode), are respectively equal to

The temperature of a gas is –50°C. To what temperature the gas should be heated so that the rms speed is increased by 3 times?

During an isothermal expansion of an ideal gas

In thermodynamics, heat and work are:

A sample of gas is at 0°C. To what temperature it must be raised in order to double the r.m.s. speed of the molecule

Heat is given to an ideal gas in an isothermal process. 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 positive work. E. The gas will do negative work. Choose the correct answer from the options given below:

A body with a mass 5 kg is acted upon by a force \( \mathbf{F} = (-3\hat{i} + 4\hat{j})N \). If its initial velocity at t = 0 is \( \mathbf{v} = (6\hat{i} - 12\hat{j}) \text{m/s} \), the time at which it will just have a velocity along the y-axis is

A copper block of mass 2.5 kg is heated in a furnace to a temperature of 500°C and then placed on a large ice block. What is the maximum amount (approx.) of ice that can melt? (Specific heat copper = 0.39 J/g°C heat of fusion of water = 335 J/g).

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 piece of ice falls from a height h so that it melts completely. Only one-quarter of the heat produced is absorbed by the ice and all energy of ice gets converted into heat during its fall. The value of h is: [Latent heat of ice is 3.4 × 10⁵ J/kg and g = 10 N/kg]

A diatomic gas (γ = 1.4) does 100 J of work when it is expanded isobarically. The heat given to the gas is:

What is the dimensional formula of ab–1 in the equation (P + a/V²) (V – b) = RT, where letters have their usual meaning.

The equation of state of a gas is given by \(\left(P + rac{a}{V^3} ight)\left(V - b^2 ight) = cT\), where P, V, T are pressure, volume and temperature respectively, and a, b, c are constants. The dimensions of a and b are respectively

A faulty thermometer reads freezing point and boiling point of water as −5°C and 95°C respectively. What is the correct value of temperature as it reads 60°C on faulty thermometer?

During an adiabatic process, the pressure of a gas is found to be proportional to the cube of its absolute temperature. The ratio Cₚ/Cᵥ for the gas is

The magnitude of heat exchanged by a system for the given cyclic process ABCA (as shown in figure) is (in SI unit)

In the pressure-volume (P⁻V) diagram shown below, a system undergoes a process from point A to point B along the curved path. Based on this curve, how does the work done by the system change during the process?

For Diatomic molecule which is not Rigid but has a additional vibrational Mode. Tick the correct statement.

The change in internal energy of one mole of gas when volume changes from V to 2V at constant pressure P is (γ is the adiabatic exponent)

A metal rod at a temperature of 150°C, radiates energy at a rate of 20 W. If its temperature is increased to 300°C, then it will radiate at the rate of

In an adiabatic process, no transfer of heat takes place between system and surroundings. Choose the correct option for free expansion of an ideal gas under adiabatic condition from the following.

The work done (in ergs) for the reversible expansion of one mole of an ideal gas from a volume of 10 L to 20 L at 25°C is

In an adiabatic process, no transfer of heat takes place between system and surroundings. Choose the correct option for free expansion of an ideal gas under adiabatic condition from the following.

An electric heater supplies heat to a system at a rate of 100 W. If the system performs work at a rate of 75 J/s, then the rate at which internal energy increases will be:

An oxygen cylinder of volume 30 litre has 18.20 moles of oxygen. After some oxygen is withdrawn from the cylinder, its gauge pressure drops to 11 atmospheric pressure at temperature 27°C. The mass of the oxygen withdrawn from the cylinder is nearly equal to: [Given, R = 100/12 J mol⁻¹K⁻¹, and molecular mass of O₂ = 32, 1 atm pressure = 1.01 × 10⁵ N/m²]

Two gases A and B are filled at the same pressure in separate cylinders with movable pistons of radius rₐ and rᵦ, respectively. On supplying an equal amount of heat to both the systems reversibly under constant pressure, the pistons of gas A and B are displaced by 16 cm and 9 cm, respectively. If the change in their internal energy is the same, then the ratio rₐ/rᵦ is equal to

A thermodynamic system is taken through the cycle abcd. The work done by the gas along the path bc is:

A Carnot engine has an efficiency of 50% when its source is at a temperature 327° C. The temperature of the sink is :

An ideal gas undergoes four different processes from the same initial state as shown in the figure below. Those processes are adiabatic, isothermal, isobaric and isochoric. The curve which represents the adiabatic process among 1, 2, 3 and 4 is:

Match Column - I and Column - II and choose the correct match from the given choices.

Two cylinders A and B of equal capacity are connected to each other via a stop cock. A contains an ideal gas at standard temperature and pressure. B is completely evacuated. The entire system is thermally insulated. The stop cock is suddenly opened. The process is:

The average thermal energy for a mono-atomic gas is : (k_B is Boltzmann constant and T, absolute temperature)

In which of the following processes, heat is neither absorbed nor released by a system?

The efficiency of an ideal heat engine working between the freezing point and boiling point of water, is

A sample of 0.1 g of water at 100°C and normal pressure (1.013 × 10⁵ Nm⁻²) requires 54 cal of heat energy to convert to steam at 100°C. If the volume of the steam produced is 167.1 cc, the change in internal energy of the sample, is

The volume (V) of a monatomic gas varies with its temperature (T), as shown in the graph. The ratio of work done by the gas, to the heat absorbed by it, when it undergoes a change from state A to state B, is

A Carnot engine having an efficiency of 1/10 as heat engine, is used as a refrigerator. If the work done on the system is 10 J, the amount of energy absorbed from the reservoir at lower temperature is:

Thermodynamics processes are indicated in the following diagram. Match the following:

A gas mixture consists of 2 moles of O₂ and 4 moles of Ar at temperature T. Neglecting all vibrational modes, the total internal energy of the system is

A refrigerator works between 4 °C and 30 °C. It is required to remove 600 calories of heat every second in order to keep the temperature of the refrigerated space constant. The power required is [Take 1 cal = 4.2 joules]

A gas is compressed isothermally to half its initial volume. The same gas is compressed separately through an adiabatic process until its volume is again reduced to half. Then

A black body is at a temperature of 5760 K. The energy of radiation emitted by the body at wavelength 250 nₘ is U₁, at wavelength 500 nₘ is U₂ and that at 1000 nₘ is U₃. Wien’s constant, b = 2.88 × 10⁶ nmK. Which of the following is correct?

Figure below shows two paths that may be taken by a gas to go from a state A to a state C. In process AB, 400 J of heat is added to the system and in process BC, 100 J of heat is added to the system. The heat absorbed by the system in the process AC will be

One mole of an ideal diatomic gas undergoes a transition from A to B along a path AB as shown in the figure. The change in internal energy of the gas during the transition is

A Carnot engine having an efficiency of 1/10 as heat engine, is used as a refrigerator. If the work done on the system is 10 J, the amount of energy absorbed from the reservoir at lower temperature is:

The ratio of the specific heats \( rac{C_p}{C_v} = \gamma \) in terms of degrees of freedom (n) is given by