When an ideal gas is compressed adiabatically, its temperature rises: the molecules on an average have more kinetic energy than before. The kinetic energy increases:
1. | because of collisions with moving parts of the wall only. |
2. | because of collisions with the entire wall. |
3. | because the molecules get accelerated in their motion inside the volume. |
4. | because of the redistribution of energy amongst the molecules. |
\(1\) mole of an ideal gas is contained in a cubical volume V, ABCDEFGH at \(300\) K (figure). One face of the cube (EFGH) is made up of a material which totally absorbs any gas molecule incident on it. At any given time:
1. | the pressure on EFGH would be zero. |
2. | the pressure on all the faces will be equal. |
3. | the pressure on EFGH would be double the pressure on ABCD. |
4. | the pressure on EFGH would be half that on ABCD. |
Diatomic molecules like hydrogen have energies due to both translational as well as rotational motion. From the equation in kinetic theory, \(PV = \dfrac{2}{3}E\) \(E\) is:
1. | the total energy per unit volume. |
2. | only the translational part of energy because rotational energy is very small compared to translational energy. |
3. | only the translational part of the energy because during collisions with the wall, pressure relates to change in linear momentum. |
4. | the translational part of the energy because rotational energies of molecules can be of either sign and its average over all the molecules is zero. |
The mean free path \(l\) for a gas molecule depends upon the diameter, \(d\) of the molecule as:
1. | \(l\propto \dfrac{1}{d^2}\) | 2. | \(l\propto d\) |
3. | \(l\propto d^2 \) | 4. | \(l\propto \dfrac{1}{d}\) |
Heat is associated with:
1. | kinetic energy of random motion of molecules. |
2. | kinetic energy of orderly motion of molecules. |
3. | total kinetic energy of random and orderly motion of molecules. |
4. | kinetic energy of random motion in some cases and kinetic energy of orderly motion in other cases. |
If \(C_p\) and \(C_v\) denote the specific heats (per unit mass) of an ideal gas of molecular weight \(M\) (where \(R\) is the molar gas constant), the correct relation is:
1. \(C_p-C_v=R\)
2. \(C_p-C_v=\frac{R}{M}\)
3. \(C_p-C_v=MR\)
4. \(C_p-C_v=\frac{R}{M^2}\)
The ratio of the average translatory kinetic energy of He gas molecules to gas molecules is:
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4. 1
Two closed containers of equal volume are filled with air at pressure and temperature . Both are connected by a narrow tube. If one of the containers is maintained at temperature and the other at temperature T, then new pressure in the container will be:
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The rms speed of the molecules of an enclosed gas is \(v\). What will be the rms speed if the pressure is doubled, keeping the temperature constant?
1. | \(v \over 2\) | 2. | \(v\) |
3. | \(2v\) | 4. | \(4v\) |
To find out the degree of freedom, the correct expression is:
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