CBSE Class 11 Physics Gravitation Worksheet Set 06

TOPIC :GRAVITATION

SECTION – A CONCEPTUAL AND APPLICATION TYPE QUESTIONS

1. 13. Why weight of a body becomes zero at the centre of earth ?

2. 14. Can a pendulum vibrate in an artificial satellite ?

3. 15. Imagine a spacecraft going from the earth to the moon . How does its weight vary as it goes from the earth ?

4. Difference between gravitational potential and gravitational field.

5. 16. What is the value of gravitational potential energy at infinity ?

6 17. The gravitational potential energy of a body at a point in gravitational field of another body is GMm/r . What does the negative sign indicate ?

7. State Kepler’s Laws of Planetary motion .

8. Write two salient features of escape velocity ?

9. 18. The escape velocity of a body when projected from earth’s surface is 11.2 km/s. If it is projected at an angle of 500 from the horizontal , what will be the escape velocity ?

10. Name two factors which determine whether a planet would have an atmosphere or not ?

11. What is Geosynchronous satellite ?

12. What is a parking orbit ?

13. Two artificial satellites are revolving around the earth , one closer to its surface and the other away from it . Which has larger speed ?

14. The gravitational potential energy of a body at a point in gravitational field of another body is GMm/r . What does the negative sign indicate ?

SECTION – B NUMERICAL PROBLEMS

1. Find the percentage decrease in weight of a body when taken to a height of 32km abovethe surface of earth , R = 6400 km.

2. At what height above the surface of the earth does the acceleration due to gravity reduce to 64 % of its value on the surface of the earth . R = 6400 km.

3. 15. How much below the surface of the earth does the acceleration due to gravity become1 % of its value at earth’s surface ?

4. 16. A body weighs 63 N on the surface of the earth. What is the gravitational force on it due to the earth at a height equal to half the radius of the earth ?

5. Assuming the earth to be a sphere of uniform mass density, how much would a body weigh half way down to the centre of the earth if it weighed 250 N on the surface?

6. Find the potential energy of a system of four particles of equal masses M placed at the corners of a square of side L. Also obtain potential at the centre of the square.

7. A rocket is fired from the earth towards the sun. At what point on its path is the gravitational force on the rocket zero? Mass of sun = 2x 1030kg, mass of the earth = 6x10²⁴kg. Neglect the effect of other planets etc. Orbital radius = 1.5x 10¹¹m.

8. A Saturn year is 29.5 times the earth year. How far is the Saturn from the sun if the earth is 1.5 x 10⁸km away from the sun?

9. The escape velocity of a projectile on earth’s surface is 11.2 kms^-1. A body is projected out with thrice this speed. What is the speed of the body far away from the earth? Ignore the presence of the sun other planets.

Please click on below link to download CBSE Class 11 Physics Gravitation Worksheet Set F