148497
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
1 adiabatic
2 isochoric
3 isobaric
4 isothermal
Explanation:
A Free expansion i.e. expansion against vacuum is adiabatic in nature for all type of gases. It should be noted that temperature final temp is equal to initial temp for ideal gases. Free expansion $\mathrm{dW}=0$ $\mathrm{dQ}=\mathrm{dU}+\mathrm{dW}$
NEET National-2019
Thermodynamics
148499
If $\Delta U$ and $\Delta W$ represent the increase in internal energy and work done by the system respectively in a thermodynamical process, which of the following is true?
1 $\Delta \mathrm{U}=-\Delta \mathrm{W}$, in an adiabatic process
2 $\Delta \mathrm{U}=\Delta \mathrm{W}$, in an isothermal process
3 $\Delta \mathrm{U}=\Delta \mathrm{W}$, in an adiabatic process
4 $\Delta \mathrm{U}=-\Delta \mathrm{W}$, in an isothermal process
Explanation:
A From the first law of thermodynamics $\Delta \mathrm{Q}=\Delta \mathrm{U}+\Delta \mathrm{W}$ $\Delta \mathrm{Q}=0$ for adiabatic process So, $\quad 0=\Delta \mathrm{U}+\Delta \mathrm{W}$ $\Delta \mathrm{U}=-\Delta \mathrm{W}$
AIPMT-2010
Thermodynamics
148437
The correct relation between $\gamma=\frac{c_{p}}{c_{v}}$ and temperature $\mathbf{T}$ is :
1 $\gamma \alpha \mathrm{T}^{\circ}$
2 $\gamma \alpha \frac{1}{\mathrm{~T}}$
3 $\gamma \alpha \mathrm{T}$
4 $\gamma \alpha \frac{1}{\sqrt{\mathrm{T}}}$
Explanation:
A $\gamma$ is dimensionless quantity, it is ratio of specific heats, hence it will not depend on temperature So $\gamma$ for given gas remains constant.
JEE Main-31.01.2023
Thermodynamics
148456
The temperature of the system decreases in the process of
1 free expansion
2 adiabatic expansion
3 isothermal expansion
4 isothermal compression
Explanation:
B In an adiabatic expansion since no heat is supplied from outside, therefore the energy for the expansion of the gas is taken from the gas itself, it means the internal energy of an ideal gas undergoing in an adiabatic expansion decreases, and because the internal energy of an ideal gas depends only on the temperature, Therefore its temperature must decreases. That is why the temperature of the system decreases in the process of adiabatic expansion.
148497
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
1 adiabatic
2 isochoric
3 isobaric
4 isothermal
Explanation:
A Free expansion i.e. expansion against vacuum is adiabatic in nature for all type of gases. It should be noted that temperature final temp is equal to initial temp for ideal gases. Free expansion $\mathrm{dW}=0$ $\mathrm{dQ}=\mathrm{dU}+\mathrm{dW}$
NEET National-2019
Thermodynamics
148499
If $\Delta U$ and $\Delta W$ represent the increase in internal energy and work done by the system respectively in a thermodynamical process, which of the following is true?
1 $\Delta \mathrm{U}=-\Delta \mathrm{W}$, in an adiabatic process
2 $\Delta \mathrm{U}=\Delta \mathrm{W}$, in an isothermal process
3 $\Delta \mathrm{U}=\Delta \mathrm{W}$, in an adiabatic process
4 $\Delta \mathrm{U}=-\Delta \mathrm{W}$, in an isothermal process
Explanation:
A From the first law of thermodynamics $\Delta \mathrm{Q}=\Delta \mathrm{U}+\Delta \mathrm{W}$ $\Delta \mathrm{Q}=0$ for adiabatic process So, $\quad 0=\Delta \mathrm{U}+\Delta \mathrm{W}$ $\Delta \mathrm{U}=-\Delta \mathrm{W}$
AIPMT-2010
Thermodynamics
148437
The correct relation between $\gamma=\frac{c_{p}}{c_{v}}$ and temperature $\mathbf{T}$ is :
1 $\gamma \alpha \mathrm{T}^{\circ}$
2 $\gamma \alpha \frac{1}{\mathrm{~T}}$
3 $\gamma \alpha \mathrm{T}$
4 $\gamma \alpha \frac{1}{\sqrt{\mathrm{T}}}$
Explanation:
A $\gamma$ is dimensionless quantity, it is ratio of specific heats, hence it will not depend on temperature So $\gamma$ for given gas remains constant.
JEE Main-31.01.2023
Thermodynamics
148456
The temperature of the system decreases in the process of
1 free expansion
2 adiabatic expansion
3 isothermal expansion
4 isothermal compression
Explanation:
B In an adiabatic expansion since no heat is supplied from outside, therefore the energy for the expansion of the gas is taken from the gas itself, it means the internal energy of an ideal gas undergoing in an adiabatic expansion decreases, and because the internal energy of an ideal gas depends only on the temperature, Therefore its temperature must decreases. That is why the temperature of the system decreases in the process of adiabatic expansion.
148497
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
1 adiabatic
2 isochoric
3 isobaric
4 isothermal
Explanation:
A Free expansion i.e. expansion against vacuum is adiabatic in nature for all type of gases. It should be noted that temperature final temp is equal to initial temp for ideal gases. Free expansion $\mathrm{dW}=0$ $\mathrm{dQ}=\mathrm{dU}+\mathrm{dW}$
NEET National-2019
Thermodynamics
148499
If $\Delta U$ and $\Delta W$ represent the increase in internal energy and work done by the system respectively in a thermodynamical process, which of the following is true?
1 $\Delta \mathrm{U}=-\Delta \mathrm{W}$, in an adiabatic process
2 $\Delta \mathrm{U}=\Delta \mathrm{W}$, in an isothermal process
3 $\Delta \mathrm{U}=\Delta \mathrm{W}$, in an adiabatic process
4 $\Delta \mathrm{U}=-\Delta \mathrm{W}$, in an isothermal process
Explanation:
A From the first law of thermodynamics $\Delta \mathrm{Q}=\Delta \mathrm{U}+\Delta \mathrm{W}$ $\Delta \mathrm{Q}=0$ for adiabatic process So, $\quad 0=\Delta \mathrm{U}+\Delta \mathrm{W}$ $\Delta \mathrm{U}=-\Delta \mathrm{W}$
AIPMT-2010
Thermodynamics
148437
The correct relation between $\gamma=\frac{c_{p}}{c_{v}}$ and temperature $\mathbf{T}$ is :
1 $\gamma \alpha \mathrm{T}^{\circ}$
2 $\gamma \alpha \frac{1}{\mathrm{~T}}$
3 $\gamma \alpha \mathrm{T}$
4 $\gamma \alpha \frac{1}{\sqrt{\mathrm{T}}}$
Explanation:
A $\gamma$ is dimensionless quantity, it is ratio of specific heats, hence it will not depend on temperature So $\gamma$ for given gas remains constant.
JEE Main-31.01.2023
Thermodynamics
148456
The temperature of the system decreases in the process of
1 free expansion
2 adiabatic expansion
3 isothermal expansion
4 isothermal compression
Explanation:
B In an adiabatic expansion since no heat is supplied from outside, therefore the energy for the expansion of the gas is taken from the gas itself, it means the internal energy of an ideal gas undergoing in an adiabatic expansion decreases, and because the internal energy of an ideal gas depends only on the temperature, Therefore its temperature must decreases. That is why the temperature of the system decreases in the process of adiabatic expansion.
148497
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
1 adiabatic
2 isochoric
3 isobaric
4 isothermal
Explanation:
A Free expansion i.e. expansion against vacuum is adiabatic in nature for all type of gases. It should be noted that temperature final temp is equal to initial temp for ideal gases. Free expansion $\mathrm{dW}=0$ $\mathrm{dQ}=\mathrm{dU}+\mathrm{dW}$
NEET National-2019
Thermodynamics
148499
If $\Delta U$ and $\Delta W$ represent the increase in internal energy and work done by the system respectively in a thermodynamical process, which of the following is true?
1 $\Delta \mathrm{U}=-\Delta \mathrm{W}$, in an adiabatic process
2 $\Delta \mathrm{U}=\Delta \mathrm{W}$, in an isothermal process
3 $\Delta \mathrm{U}=\Delta \mathrm{W}$, in an adiabatic process
4 $\Delta \mathrm{U}=-\Delta \mathrm{W}$, in an isothermal process
Explanation:
A From the first law of thermodynamics $\Delta \mathrm{Q}=\Delta \mathrm{U}+\Delta \mathrm{W}$ $\Delta \mathrm{Q}=0$ for adiabatic process So, $\quad 0=\Delta \mathrm{U}+\Delta \mathrm{W}$ $\Delta \mathrm{U}=-\Delta \mathrm{W}$
AIPMT-2010
Thermodynamics
148437
The correct relation between $\gamma=\frac{c_{p}}{c_{v}}$ and temperature $\mathbf{T}$ is :
1 $\gamma \alpha \mathrm{T}^{\circ}$
2 $\gamma \alpha \frac{1}{\mathrm{~T}}$
3 $\gamma \alpha \mathrm{T}$
4 $\gamma \alpha \frac{1}{\sqrt{\mathrm{T}}}$
Explanation:
A $\gamma$ is dimensionless quantity, it is ratio of specific heats, hence it will not depend on temperature So $\gamma$ for given gas remains constant.
JEE Main-31.01.2023
Thermodynamics
148456
The temperature of the system decreases in the process of
1 free expansion
2 adiabatic expansion
3 isothermal expansion
4 isothermal compression
Explanation:
B In an adiabatic expansion since no heat is supplied from outside, therefore the energy for the expansion of the gas is taken from the gas itself, it means the internal energy of an ideal gas undergoing in an adiabatic expansion decreases, and because the internal energy of an ideal gas depends only on the temperature, Therefore its temperature must decreases. That is why the temperature of the system decreases in the process of adiabatic expansion.
