Thermodynamics

If the temperature of a gas is doubled at constant pressure, what happens to its volume according to the concept of thermal expansion?

A rectangular metal sheet has a length $L$ and width $W$. On heating, both $L$ and $W$ increase. This is an example of:

The expansion of which of the following is most noticeable in daily life applications like thermometers?

The coefficient of cubical expansion of a liquid is:

A brass disc fits exactly in a hole in a steel plate at $20^\circ C$. If the system is cooled to $0^\circ C$, what happens? (Given $\alpha_{brass} > \alpha_{steel}$)

A piece of copper and a piece of glass are heated to the same temperature. Which one will expand more?

The expansion of a gas at constant pressure is called:

Two cylinders of the same length and same material, one hollow and one solid, are heated to the same temperature. Which one expands more in length?

A bimetallic strip of length $L$ is made of two metals with expansion coefficients $\alpha_1$ and $\alpha_2$. If the strip is heated by $\Delta T$, the difference in the lengths of the two strips becomes:

A vessel of volume $V$ is half-filled with a liquid. If the volume of the empty part is to remain constant at all temperatures, the coefficient of volume expansion of the liquid $\gamma$ must be related to the linear expansion of the vessel $\alpha$ by:

If the temperature of a body increases by $10^{\circ}C$, the increase in its temperature on the Kelvin scale is:

A calorimeter is usually polished from the outside to:

What happens to the internal potential energy of molecules during the boiling of water?

If the heat capacity of a body is $50 \text{ J/K}$, how much heat is required to raise its temperature by $2 \text{ K}$?

The unit of molar heat capacity is:

What is the amount of heat required to melt $2 \text{ kg}$ of ice at $0^{\circ}C$? ($L_f = 3.36 \times 10^5 \text{ J/kg}$)

The freezing point of a substance decreases when pressure is increased if:

A calorimeter contains $0.1 \text{ kg}$ of water at $15^{\circ}C$. $0.16 \text{ kg}$ of a substance at $80^{\circ}C$ is dropped into it, and the temperature rises to $35^{\circ}C$. Then, a $0.02 \text{ kg}$ block of ice at $0^{\circ}C$ is added. The final temperature is $25^{\circ}C$. Calculate the specific heat of the substance.

What is the result of mixing $10 \text{ g}$ of ice at $-10^{\circ}C$ with $1 \text{ g}$ of steam at $100^{\circ}C$ in an isolated system?

A $50 \text{ g}$ mass of steam at $120^{\circ}C$ is mixed with $200 \text{ g}$ of ice at $-20^{\circ}C$. What is the final temperature? (Specific heat of steam $= 0.5 \text{ cal/g}^{\circ}C$, ice $= 0.5 \text{ cal/g}^{\circ}C$, water $= 1 \text{ cal/g}^{\circ}C$)

Which of the following is the correct unit for the Universal Gas Constant ($R$)?

Thermodynamics mainly studies the transformation of:

If the volume of a system increases, the work done by the system is:

Which property is independent of the mass of the substance in the system?

In an isobaric process, $100 \text{ J}$ of heat is supplied to a system. If the system does $20 \text{ J}$ of work, the increase in internal energy is:

Specific heat of a gas during an isothermal process is:

If the internal energy of a system remains constant during a process, the work done by the system must be equal to:

If $\Delta U$ and $W$ represent the increase in internal energy and work done by the system respectively in a thermodynamic process, which of the following is true for an adiabatic process?

A gas is compressed at a constant pressure of $50 \text{ N/m}^2$ from a volume of $10 \text{ m}^3$ to $4 \text{ m}^3$. Energy of $100 \text{ J}$ is then added to the gas by heating. Its internal energy:

When a gas expands into a vacuum (free expansion), which of the following is true?

Which of the following is the condition for a process to be perfectly adiabatic?

If the temperature of a gas remains constant during expansion, the process is:

In an adiabatic expansion, the work done by the gas ($dW$) and change in internal energy ($dU$) are related as:

The ratio $C_p / C_v$ is always:

The mathematical expression for the slope of the $P-V$ curve for an adiabatic process at point $(P, V)$ is:

The mathematical expression for the slope of the $P-V$ curve for an isothermal process at point $(P, V)$ is:

During the free expansion of an ideal gas into an evacuated chamber, which of the following is true?

During the adiabatic compression of a gas, the work done on the gas is $150\text{ J}$. What is the change in internal energy of the gas?

A gas is compressed adiabatically until its temperature doubles. What is the ratio of final pressure to initial pressure if $\gamma = 1.5$?

The ratio of the speed of sound in a gas under adiabatic conditions to that under isothermal conditions is:

A Carnot cycle consists of how many adiabatic processes?

The second law of thermodynamics is essentially a law of:

When a gas is heated at constant volume, its entropy:

In a refrigerator, the temperature of the working substance is:

A total of $1000\text{ J}$ of heat is transferred from a hot reservoir maintained at $500\text{ K}$ to a cold reservoir at $200\text{ K}$ through a conducting rod. What is the net change in the entropy of the universe $(\Delta S_{\text{universe}})$ resulting from this process?

What is the change in entropy when $2\text{ moles}$ of an ideal gas undergo a reversible isothermal expansion from volume $V$ to $10V$ at $300\text{ K}$? (Use $R = 8.31\text{ J/mol\cdot K}$ and $\ln(10) \approx 2.3$)

The entropy of a system decreases when:

Calculate the change in entropy of $2\text{ moles}$ of an ideal gas when it is heated from $300\text{ K}$ to $600\text{ K}$ at constant pressure. (Given $C_p = 5R/2$)

A Carnot engine has efficiency $\eta$. To double the efficiency, the temperature of the source $T_H$ must be changed to $T_H'$ (keeping $T_L$ constant). The value of $T_H'$ is:

A reversible engine takes in $Q_1$ heat at $T_1$ and $Q_2$ at $T_2$ and rejects $Q_3$ at $T_3$. What is the correct relation for this system?

What is the relationship between heat ($Q$) and work ($W$) for a heat engine cycle?

In a Carnot cycle, the final step (Adiabatic Compression) returns the working substance to its:

If a refrigerator has a COP of 5 and does $100 \, J$ of work, how much heat is removed from the cold reservoir?

The thermal reservoir in a heat engine that supplies heat is kept at temperature $T_1$. $T_1$ is called the:

The maximum possible efficiency of a heat engine is determined solely by:

A heat engine absorbs $Q_1$ heat and rejects $Q_2$ heat. If $Q_1/Q_2 = 1.5$, what is the efficiency of the engine?

A heat engine operates between $800\,K$ and $400\,K$. If the source temperature is decreased by $100\,K$ and the sink temperature is decreased by $100\,K$, the efficiency will:

A heat engine receives heat from a source at $1200$ K and rejects heat to a sink at $300$ K. If the efficiency is $50\%$, what is the ratio of the actual efficiency to the maximum possible efficiency?

An irreversible engine operates between $1000$ K and $300$ K. It absorbs $1000$ J and performs $400$ J of work. What is the entropy change of the universe per cycle?

Consider a cycle on a P-V diagram that is a circle. If the maximum and minimum pressures are $P_{max}, P_{min}$ and the volumes are $V_{max}, V_{min}$, the work done per cycle is: