An ideal gas goes from state \(A\) to state \(B\) via three different processes as indicated in the \((P\text-V)\) diagram.
If \(Q_1,Q_2,Q_3\) indicate the heat absorbed by the gas along the three processes and \(\Delta U_1, \Delta U_2, \Delta U_3\) indicate the change in internal energy along the three processes respectively, then:
1. | \(Q_3>Q_2>Q_1\) and \(\Delta U_1= \Delta U_2= \Delta U_3\) |
2. | \(Q_1=Q_2=Q_3\) and \(\Delta U_1> \Delta U_2> \Delta U_3\) |
3. | \(Q_3>Q_2>Q_1\) and \(\Delta U_1> \Delta U_2> \Delta U_3\) |
4. | \(Q_1>Q_2>Q_3\) and \(\Delta U_1= \Delta U_2= \Delta U_3\) |
At a pressure of \(2\) atmospheres, a mass of diatomic gas \((\gamma = 1.4)\), is compressed adiabatically, causing its temperature to rise from \(27^{\circ}\mathrm{C}\) to \(927^{\circ}\mathrm{C}\). The pressure of the gas in the final state is:
1. 8 atm
2. 28 atm
3. 68.7 atm
4. 256 atm
A monoatomic gas at pressure P1 and volume V1 is compressed adiabatically to 1/8th its original volume. What is the final pressure of the gas?
1. P1
2. 16 P1
3. 32 P1
4. 64 P1
Which one of the following processes is reversible?
1. | Transfer of heat by radiation |
2. | Transfer of heat by conduction |
3. | Isothermal compression |
4. | Electrical heating of a nichrome wire |
An ideal gas heat engine operates in a Carnot cycle between 227ºC and 127ºC. It absorbs 6 × 104 cals of heat at higher temperatures.
The amount of heat converted to work will be?
1. 4.8 × 104 cals
2. 2.4 × 104 cals
3. 1.2 × 104 cals
4. 6 × 104 cals
When volume changes from \(V\) to \(2V\) at constant pressure(\(P\)), the change in internal energy will be:
1. \(PV\)
2. \(3PV\)
3. \(\frac{PV}{\gamma -1}\)
4. \(\frac{RV}{\gamma -1}\)
If a gas changes volume from 2 litres to 10 litres at a constant temperature of 300K, then the change in its internal energy will be:
1. | 12 J | 2. | 24 J |
3. | 36 J | 4. | 0 J |
1. | \(\Delta {U}=-{W}\) in an isothermal process. |
2. | \(\Delta {U}={W}\) in an isothermal process. |
3. | \(\Delta {U}=-{W}\) in an adiabatic process. |
4. | \(\Delta {U}={W}\) in an adiabatic process. |
The initial pressure and volume of a gas are P and V respectively. First, its volume is expanded to 4V by an isothermal process and then compressed adiabatically to volume V. The final pressure will be (γ = 1.5):
1. | 8P | 2. | 4P |
3. | P | 4. | 2P |
One mole of an ideal gas at an initial temperature of \(T\) K does \(6R\) joules of work adiabatically. If the ratio of specific heats of this gas at constant pressure and at constant volume is \(5/3\), the final temperature of the gas will be:
1. \((T-2.4)\) K
2. \((T+4)\) K
3. \((T-4)\) K
4. \((T+2.4)\) K