Kinetic Theory CBSE Questions & Answers

Kinetic Theory

This is Physics Class 11 Kinetic Theory CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
According to the law of equipartition of energy
  • A
    the total energy is equally distributed in all possible energy modes, with each mode having an average energy equal to \({{\rm{k}}_{\rm{B}}}\)T
  • B
    the total energy is equally distributed in all possible energy modes, with each mode having an average energy equal to \({3 \over 4}\) \({{\rm{k}}_{\rm{B}}}\) T
  • C
    the total energy is equally distributed in all possible energy modes, with each mode having an average energy equal to \(\frac{1}{2}{\text{ }}{{\text{k}}_{\text{B}}}{\text{T}}\)
    Correct
  • D
    the total energy is equally distributed in all possible energy modes, with each mode having an average energy equal to \({1 \over 4}\) \({{\rm{k}}_{\rm{B}}}\) T
2
The number of degrees of freedom a diatomic molecule is
  • A
    4
  • B
    6
  • C
    5.0
    Correct
  • D
    3
3
The number of degrees of freedom a monatomic molecule is
  • A
    3.0
    Correct
  • B
    4
  • C
    1
  • D
    2
4
The molar specific heat at constant volume, \({{\rm{C}}_{\rm{v}}}\) for monatomic gases is
  • A
    \({7 \over 2}\)RT
  • B
    \({3 \over 2}\)RT
    Correct
  • C
    RT
  • D
    \({5 \over 2}\)RT
5
The molar specific heat at constant volume, \({{\rm{C}}_{\rm{v}}}\) for diatomic gases is
  • A
    RT
  • B
    \({7 \over 2}\)RT
  • C
    \({5 \over 2}\)RT
    Correct
  • D
    \({3 \over 2}\)RT
6
For a rope of yield strength \({{\rm{S}}_{\rm{y}}}\) loaded in tension with weight Mg the minimum area A of the rope should be
  • A
    A \( \geq \) Mg/3 \({{\rm{S}}_{\rm{y}}}\)
  • B
    A \( \geq \) Mg/2 \({{\rm{S}}_{\rm{y}}}\)
  • C
    A \( \geq \) Mg/ \({{\rm{S}}_{\rm{y}}}\)
    Correct
  • D
    A \( \geq \) Mg \({{\rm{S}}_{\rm{y}}}\)
7
Mean free path is the
  • A
    (maximum distance + minimum distance )/ 2 between collisions
  • B
    minimum distance between collisions
  • C
    maximum distance between collisions
  • D
    average distance between collisions
    Correct
8
Approximate equation for calculating the mean free path is
  • A
    \(\lambda = {1 \over {\pi {d^2}}}\)
  • B
    \(\lambda = {1 \over {n{d^2}}}\)
  • C
    \(\lambda = {1 \over {n\pi {d^2}}}\)
    Correct
  • D
    \(\lambda = {1 \over {n\pi {d^3}}}\)
9
Estimate the fraction of molecular volume to the actual volume occupied by oxygen gas at STP. Take the diameter of an oxygen molecule to be 3 \(\mathop A\limits^0 \).
  • A
    4 \( \times \) \({\rm{1}}{0^{-{\rm{4}}}}\)
    Correct
  • B
    4.5 \( \times \) \({\rm{1}}{0^{-{\rm{4}}}}\)
  • C
    3.5 \( \times \) \({\rm{1}}{0^{-{\rm{4}}}}\)
  • D
    5 \( \times \) \({\rm{1}}{0^{-{\rm{4}}}}\)
10
Molar volume is the volume occupied by 1 mol of any (ideal) gas at standard temperature and pressure (STP : 1 atmospheric pressure, 0 \(^\circ \)C). The value of Molar volume is
  • A
    20.4 liters
  • B
    22.4 liters
    Correct
  • C
    24.4 liters
  • D
    23.7 liters
11
Figure shows plot of PV/T versus P for 1.00\( \times \)\({\rm{1}}{0^{-{\rm{3}}}}\) kg of oxygen gas at two different temperatures The dotted plot corresponds to
Question 11 figure 1
  • A
    ‘real’ gas behavior
  • B
    ‘super cooled’ gas behavior
  • C
    ‘ideal’ gas behavior
    Correct
  • D
    ‘super heated’ gas behavior
12
Figure shows plot of PV/T versus P for 1.00\( \times \)\({\rm{1}}{0^{-{\rm{3}}}}\) kg of oxygen gas at two different temperatures. Comparing \({{\rm{T}}_{\rm{1}}}\) and \({{\rm{T}}_{\rm{2}}}\)
Question 12 figure 1
  • A
    \({{\rm{T}}_{\rm{1}}}\) < \({{\rm{T}}_{\rm{2}}}\)
  • B
    \({{\rm{T}}_{\rm{1}}}\) = \({{\rm{T}}_{\rm{2}}}\)
  • C
    \({{\rm{T}}_{\rm{1}}}\) \( \geq \) \({{\rm{T}}_{\rm{2}}}\)
  • D
    \({{\rm{T}}_{\rm{1}}}\) > \({{\rm{T}}_{\rm{2}}}\)
    Correct
13
Figure shows plot of PV/T versus P for 1.00\( \times \)\({\rm{1}}{0^{-{\rm{3}}}}\) kg of oxygen gas at two different temperatures. What is the value of PV/T where the curves meet on the y-axis?
  • A
    0.26 J \({{\rm{K}}^{-{\rm{1}}}}\)
    Correct
  • B
    0.22 J \({{\rm{K}}^{-{\rm{1}}}}\)
  • C
    0.28 J \({{\rm{K}}^{-{\rm{1}}}}\)
  • D
    0.24 J \({{\rm{K}}^{-{\rm{1}}}}\)
14
An oxygen cylinder of volume 30 liters has an initial gauge pressure of 15 atm and a temperature of 27 \(^\circ \)C. After some oxygen is withdrawn from the cylinder, the gauge pressure drops to 11 atm and its temperature drops to 17 \(^\circ \)C. Estimate the mass of oxygen taken out of the cylinder (R = 8.31 J \({\rm{mo}}{{\rm{l}}^{-{\rm{1}}}}\) \({{\rm{K}}^{-{\rm{1}}}}\), molecular mass of \({{\rm{O}}_{\rm{2}}}\) = 32 u).
  • A
    0.16 kg
  • B
    0.14 kg
    Correct
  • C
    0.12 kg
  • D
    0.10 kg
15
An air bubble of volume 1.0 \({\rm{c}}{{\rm{m}}^{\rm{3}}}\) rises from the bottom of a lake 40 m deep at a temperature of 12 \(^\circ \)C. To what volume does it grow when it reaches the surface, which is at a temperature of 35 \(^\circ \)C?
  • A
    5.1 \( \times \) \({\rm{1}}{0^{-{\rm{6}}}}\) \({{\rm{m}}^{\rm{3}}}\)
  • B
    5.5 \( \times \) \({\rm{1}}{0^{-{\rm{6}}}}\) \({{\rm{m}}^{\rm{3}}}\)
  • C
    4.9 \( \times \) \({\rm{1}}{0^{-{\rm{6}}}}\) \({{\rm{m}}^{\rm{3}}}\)
  • D
    5.3 \( \times \) \({\rm{1}}{0^{-{\rm{6}}}}\) \({{\rm{m}}^{\rm{3}}}\)
    Correct