

MCQOPTIONS
Saved Bookmarks
This section includes 8 Mcqs, each offering curated multiple-choice questions to sharpen your Physics Questions and Answers knowledge and support exam preparation. Choose a topic below to get started.
1. |
A particle is kept at a distance R above the earth’s surface. What is the minimum speed with which it should be projected so that it does not return? |
A. | [(G*M)/(4*R)]1/2 |
B. | [(G*M)/(2*R)]1/2 |
C. | [(G*M)/R] 1/2 |
D. | [(2*G*M)/R]1/2 |
Answer» D. [(2*G*M)/R]1/2 | |
2. |
A planet as a radius “R” and density “P”. The escape velocity of this planet is _____ |
A. | directly proportional to P |
B. | inversely proportional to P |
C. | directly proportional to P1/2 |
D. | inversely proportional to P1/2 |
Answer» D. inversely proportional to P1/2 | |
3. |
The escape velocity of a planet depends on the radius of its orbit around the parent star. |
A. | a)True |
B. | b)False |
Answer» C. | |
4. |
The escape velocity at the event horizon of a black hole is 3×108 m/s, i.e., the velocity of light. What is the mass of the black hole if the distance from its centre to the event horizon is 18km? |
A. | 12.15 x 10-30 kg |
B. | 12.15 x 1030 kg |
C. | Infinity |
D. | Cannot be determined |
Answer» C. Infinity | |
5. |
The escape velocity of the earth is “v”. If an object is thrown vertically upwards with a velocity “kv”, what is the speed of the object at infinity? |
A. | v/(k2-1)1/2 |
B. | v(k2-1)1/2 |
C. | v2/(k2-1) |
D. | v2 (k2-1) |
Answer» C. v2/(k2-1) | |
6. |
An object is projected vertically upwards with a velocity (gr) 1/2. What is the maximum height reached by the object if “R” is the radius of the earth and “g” is the acceleration due to gravity? |
A. | R/2 |
B. | R |
C. | 2R |
D. | 4R |
Answer» C. 2R | |
7. |
What is the minimum velocity required for an object of mass “m” to escape the gravitational pull of a planet of mass “M” and radius “R” from its surface? |
A. | [(G*M)/R]1/2 |
B. | [(2*G*M)/R] 2 |
C. | [(G*M*m)/R]1/2 |
D. | [(2*G*M)/R]1/2 |
Answer» E. | |
8. |
The ratio of the radius of a planet A to that of a planet B is “r”. The ratio of acceleration due to gravity on the planets is “p”. The ratio of escape velocities of the two planets is _____ |
A. | (pr)1/2 |
B. | (p/r)1/2 |
C. | (pr) |
D. | (p/r) |
Answer» B. (p/r)1/2 | |