Competitive Exams: Physics MCQs (Practice-Test 32 of 35)

  1. In a porous plug experiment, the change in temperature of the gas depends upon

    1. its specific heat

    2. its thermal conductivity

    3. the difference in pressure on either side of the plug

    4. the rate of flow of the gas through the porous plug

  2. Consider the following statements

    1. The energy change during a reversible adiabatic process is zero.

    2. Entropy is a state function.

    3. The entropy of a thermally isolated system never decreases.

    4. The entropy change during an irreversible adiabatic process is zero.

    Of these statements

    1. 1 and 3 are correct

    2. 2, 3 and 4 are correct

    3. 2 and 4 are correct

    4. 1, 2 and 3 are correct

  3. The efficiency of the reversible cycle shown in the given figure is

    1. 16.7%

    2. 33.3%

    3. 50.0%

    4. 66.7%

  4. The percentage of lighter gases like hydrogen and helium is very small in the atmosphere of the earth. This can be explained on the basis of

    1. kinetic theory of matter

    2. temperature gradient of the atmosphere

    3. Brownian motion of the gas molecules

    4. concept of equipartition of energy

  5. Consider the following statements about Brownian motion

    1. The motion is continuous, random and irregular.

    2. No two particles, execute the same motion.

    3. Smaller the particles, faster the motion.

    4. The motion is dependent on external influences.

    Of these statements

    1. 2, 3 and 4 are correct

    2. 1, 3 and 4 are correct

    3. 1, 2 and 4 are correct

    4. 1, 2 and 3 are correct

  6. Consider the following statements: Viscosity of a

    1. gas increases with temperature.

    2. gas decreases with temperature.

    3. liquid generally decreases rapidly with temperature.

    4. liquid generally increases rapidly with temperature.

    Of these statements

    1. 1 and 3 are correct

    2. 1 and 4 are correct

    3. 2 and 3 are correct

    4. 2 and 4 are correct

  7. Which of the following pairs are correctly. Matched?

    1. Law of liquefaction of gases: Joule-Kelvin

    2. Law of distribution of speed: Maxwell

    3. Law of equipartition of energy: Boltzmann

    Select the correct answer from the codes given below

    1. 2 and 3

    2. 1 and 3

    3. 1 and 2

    4. 1, 2 and 3

  8. In the equation of state for real gases (P + a/a2) (v-b) = RT the constant ‘a’ determines

    1. Vc alone

    2. Pc alone

    3. Tc alone

    4. Vc and Pc

  9. A radiating gas at temperature T (Kelvin) fills a cavity of volume V. If the system expanded adiabatically and reversibly to a volume of 8V, then the temperature would change by a factor of

    1. 8

    2. ½

    3. 2

  10. Match List I (Physical quantity) with List II (Units) and select the correct answer

    List-I List-II
    1. Mass

    2. Torque

    3. Impulse

    4. Viscosity

    1. Slug

    2. Poise

    3. Newton second

    4. Newton meter

    5. Newton

    • A
    • B
    • C
    • D
      • 1
      • 4
      • 3
      • 2
      • 5
      • 4
      • 2
      • 1
      • 1
      • 5
      • 3
      • 2
      • 5
      • 2
      • 4
      • 1