2nd Year Physics Chapter 2 Test16. Statistical Mechanics and Thermodynamics

Q1. Multiple choice questions (Attempt all · 10 × 1 = 10)

1. Statistical mechanics connects microscopic details with:
   1. Microscopic observables only
   2. Macroscopic observables only
   3. Both microscopic and macroscopic observables
   4. None of these
2. The rms speed of gas molecules depends on:
   1. Temperature only
   2. Molar mass only
   3. Both temperature and molar mass
   4. Pressure only
3. Average velocity of molecules in a gas:
   1. zero
   2. positive
   3. negative
   4. infinity
4. The equation of state of n moles of an ideal gas is PV = nRT, where R is a constant. The SI unit for R is:
   1. Jkg⁻¹K⁻¹
   2. Jg⁻¹k⁻¹
   3. JK⁻¹ mol⁻¹
   4. JK⁻¹ per molecule
5. The pressure is exerted by the gas on the walls of the container because its molecules:
   1. lose kinetic energy
   2. stick to the walls
   3. on collision with the walls, there is a change in momentum of gas molecules
   4. on collision with the walls, gas molecules exert no force on wall
6. Superconductivity was first discovered in:
   1. 1911
   2. 1921
   3. 1931
   4. 1941
7. Gas that obeys PV = nRT is called:
   1. Real gas
   2. Ideal gas
   3. Non-ideal gas
   4. Van der Waals gas
8. What is the approximate surface temperature of a hot neutron star?
   1. Several million degrees Celsius
   2. Room temperature
   3. 1000°C
   4. 0°C
9. Which of the following is the electrical resistance of the superconductor below critical temperature?
   1. Finite
   2. Large
   3. Zero
   4. Infinity
10. What creates degeneracy pressure in white dwarfs?
    1. Thermal expansion
    2. Electron behavior due to Pauli Exclusion Principle
    3. Fusion of atoms
    4. Magnetic fields