11th class (Fsc) Physics unit 11 MCQs
chapter 11 MCQs 11th Class Physics
Heat and Thermodynamics:
1. At constant temperature and pressure, if volume of given mass of a gas is doubled, then density of the gas becomes:
a. ½ original
b. Double
c. Unchanged
d. ¼ of original
2. For a gas obeying Boyle’s law, if the pressure is doubled, the volume becomes:
a. One half
b. Doubled
c. Remains the same
d. Three-fold
3. The relation for absolute temperature of a gas is given by:
a. T= 3/2k <1/2 mv2>
b. T= 2/3k <1/2 mv2>
c. T= 3k/2 <1/2 mv2>
d. T= 2k/3 <1/2 mv2>
4. Average translation kinetic energy of gas molecule is:
a. 2/3 KT
b. 1/2 KT
c. 3/2 KT
d. KT
5. The ideal gas law is:
a. PV= n RT
b. PV=NVK
c. P=n RT
d. P=NKT
6. The value of Boltzman’s constant is:
a. 1.38 x 10-23 J/mol.k
b. 1.38 x 10-23 J/k
c. 1.38 x 1023 J/mol.k
d. 1.38 x 1023 J/k
7. Pressure of gas is given as:
a. 1/3 Ne < V2 >
b. 1/3 ρ < V2 >
c. 2/3 ρ < V2 >
d. None of these
8. At constant temperature and pressure, if volume of given mass of a gas is doubled then:
a. ½ original
b. Doubled
c. Unchanged
d. ¼ original
9. Temperature of a gas is increased from 27oC to 127oC. The ratio of its mean K.E will be:
a. 4/3
b. 3/4
c. 10/9
d. 9/16
10. What is the ratio called, when Universal gas constant (R) is divided by Avogadro’s number (N)?
a. Rydberg’s constant
b. Plank’s constant
c. Van der Waal’s constant
d. Boltzmann’s constant
11. At constant temperature, if pressure of a given mass of gas is halved, then its volume becomes:
a. Four times
b. Halved
c. Constant
d. Doubled
12. SI units of pressure of gas is:
a. N2/m
b. Nm-2
c. N2 .m
d. Nm
13. Pascal is the unit of:
a. Tension
b. Pressure
c. Weight
d. Force
14. According to Charles law:
a. P ∝ 1/T
b. V ∝ T
c. P ∝ 1/V
d. V ∝ n
15. The Mean kinetic energy of gas is zero at:
a. 100 K
b. 0oC
c. 100oC
d. -273oC
16. Boltzman constant ‘k’ has same unit as:
a. Entropy
b. Temperature
c. Pressure
d. Energy
17. The internal energy of system does not depend on:
a. Path
b. Temperature
c. Initial and final state
d. Pressure
18. The internal energy of piece of lead when beaten by hammer will:
a. Remains constant
b. Increase
c. First increases and then decrease
d. Decrease
19. For an ideal gas, the internal energy is directly proportional to:
a. Mass
b. Pressure
c. Temperature
d. Volume
20. A gas performs 10J of work and at the same time has its internal energy increased by 320 energy is:
a. 100 J
b. 10 J
c. -200 J
d. -10 J
21. A diatomic gas molecule has:
a. Vibrational energy only
b. Translation energy only
c. Rotational energy only
d. all of these
22. The sum of all types of energies of all molecules of a substance is called:
a. Power
b. Heat energy
c. Internal energy
d. Efficiency
23. For ideal gas, the potential energy associated with its molecules is:
a. 1/2kx2o
b. Maximum
c. 1/2kxo
d. zero
24. The SI unit of product of pressure and volume is:
a. Pascal
b. walt
c. Newton
d. Joule
25. Heat is form of:
a. Energy
b. Power
c. Torque
d. Momentum