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This section includes 9 Mcqs, each offering curated multiple-choice questions to sharpen your Physics knowledge and support exam preparation. Choose a topic below to get started.
1. |
Boyle s law can be deduced from kinetic theory. True or False? |
A. | True |
B. | False |
Answer» B. False | |
2. |
What is the number of molecules in 3 cubic metre of a gas at 3atm & 27 C? |
A. | 2.17*10<sup>-20</sup> |
B. | 6.38*10<sup>-20</sup> |
C. | 3.86*10<sup>-20</sup> |
D. | 4.58*10<sup>-20</sup> |
Answer» B. 6.38*10<sup>-20</sup> | |
3. |
A container has 3 gases whose mass ratio is 1:3:5. What is the ratio of mean square speed of the molecules of two gases? Their atomic masses are 20u, 30u & 40u corresponding to the order in which the ratios are given. |
A. | 2:3:4 |
B. | 4:3:2 |
C. | 2: 3: 2 |
D. | 2: 3:2 |
Answer» C. 2: 3: 2 | |
4. |
Average kinetic energy of a gas depends on which of the following factors? |
A. | Nature of gas |
B. | Temperature |
C. | Pressure |
D. | Volume |
Answer» C. Pressure | |
5. |
The number of molecules per unit volume in the sample is 20. The mass of each molecule is 10-20kg. The mean of speed squared is 4m2/s2. What is the value of internal energy of the gas? Assume volume of container is 0.02m3. |
A. | 0.8*10<sup>-20</sup>J |
B. | 0.53*10<sup>-20</sup>J |
C. | 0.01*10<sup>-20</sup>J |
D. | 0.45*10<sup>-20</sup>J |
Answer» B. 0.53*10<sup>-20</sup>J | |
6. |
Which of the following is not an assumption of KTG? |
A. | Time spent during collision is negligibly small |
B. | All gases are made up of molecules moving randomly in all directions |
C. | Molecules do not collide with each other |
D. | Molecules collide elastically with the wall |
Answer» D. Molecules collide elastically with the wall | |
7. |
Consider a gas inside a box. It exerts some pressure on its walls. Find this value. GIven that number of molecules per unit volume be 20, mass of each molecule 10-20kg, vx2 = 1m2/s2. |
A. | 20*10<sup>-20</sup>Pa |
B. | 20/3*10<sup>-20</sup>Pa |
C. | 20/3*10<sup>-19</sup>Pa |
D. | 20*10<sup>-19</sup>Pa |
Answer» B. 20/3*10<sup>-20</sup>Pa | |
8. |
Consider a gas enclosed in a box. Let the walls have an area of 0.01m2. Let s say a few molecules having their x-component of velocity =2m/s, hit a wall parallel to the yz plane. What will be the value of force on the wall in time dt? Let the number of molecules per unit volume be 10 & mass of each molecule be 10-20kg. |
A. | 4*10<sup>-19</sup>N |
B. | 4*10<sup>-21</sup>N |
C. | 4/3*10<sup>-21</sup>N |
D. | 4/3*10<sup>-19</sup>N |
Answer» C. 4/3*10<sup>-21</sup>N | |
9. |
Consider a gas enclosed in a box. A molecule of mass m, having a velocity -2i+3j+4k collides with a wall parallel to the xz plane. What will be its velocity after collision and its change in momentum? i,j & k are unit vectors along the x,y & z axis. |
A. | -2i-3j+4k, -6mj |
B. | 2i+3j-4k, -6mj |
C. | -2i-3j+4k, 6mj |
D. | 2i+3j-4k, 6mj |
Answer» B. 2i+3j-4k, -6mj | |