Gravitation Mock Test – Class 11 Physics

1. A satellite moves in a circular orbit of radius . Its angular momentum about the planet’s centre is . In a new circular orbit of radius , its angular momentum becomes

2. A satellite is at a height above Earth’s surface. If is the surface value, the gravitational acceleration at the satellite is

3. The expression can represent the binding energy of a circular satellite orbit. Its SI unit is

4. Gravitational potential at a point is defined as

5. A proposed formula for escape speed is . It is rejected because has the dimension of

6. The total mechanical energy of a satellite in a circular orbit is

7. In a circular satellite orbit, the acceleration is toward Earth’s centre while the velocity is tangential. The angle between acceleration and velocity is

8. The following statements refer to Kepler’s laws.
I. The first law describes the shape of the orbit.
II. The second law connects equal areas with equal time intervals.
III. The third law relates to the cube of orbital size.
The suitable option is

9. In the derivation of , the orbital speed is replaced by

10. A body is at height above Earth’s surface. The gravitational potential at its position is

11. A graph of orbital speed against orbital radius for circular satellites is decreasing. If the horizontal axis is changed to , the relation between and becomes

12. A planet has the same surface gravity as Earth but twice Earth’s radius. Its near-surface orbital speed compared with Earth’s near-surface orbital speed is

13. Binding energy of a satellite in a circular orbit is best described as the energy required to

14. A graph is drawn for a fixed arrangement of several source masses. The horizontal axis is the test mass , and the vertical axis is the net gravitational force magnitude on it. If the source masses and distances are unchanged, the graph should be

15. The dimension of the universal gravitational constant is

16. The escape speed from a planet is . If the planet’s mass is kept fixed and its radius is made one-fourth, the new escape speed becomes

17. A low-orbit satellite has local gravitational acceleration , yet a loose object inside it appears weightless. The best explanation is that

18. In the equality , the cancellation of means that

19. A body is projected from the surface of a planet of radius with speed . It reaches a maximum height above the surface. The value of is

20. The term gravitational gradient in the context of tides refers to

21. The unit of can be obtained from . It is

22. The table gives values of height for the same Earth.

The corresponding values of are

23. A planet has mass and radius . A projectile is fired from its surface with speed equal to the circular orbital speed just above the surface, but vertically upward. The maximum height reached above the surface is

24. Two satellites of equal mass orbit the same planet in circular orbits. Satellite has orbital radius , and satellite has orbital radius . The ratio of their binding energies is

25. A stone released from rest near Earth falls downward mainly because

26. The SI unit of gravitational field intensity can be written as

27. From , the surface value of is

28. A circular satellite orbit has . After a maneuver, the satellite just escapes from the same radius. The minimum extra energy supplied by the engine is

29. Assertion: The gravitational field inside a thin uniform spherical shell is zero everywhere. Reason: At an interior point, vector contributions from different parts of the shell cancel due to spherical symmetry.

30. Two masses and are placed at points and . A test mass is placed on the -axis outside the interval on the left side of . The net gravitational field there can be zero

31. In a circular satellite orbit, the kinetic energy of a satellite of mass around a planet of mass at orbital radius is

32. A planet has density and radius . Planet has density and radius . The ratio of their escape speeds is

33. Consider these statements about applying superposition to gravitational forces.
I. Each source mass exerts its force on the test mass independently.
II. The net force is obtained by scalar addition only.
III. Symmetric arrangements can give zero net force even though individual forces are nonzero.
The suitable option is

34. In a Cavendish-type experiment, the main purpose is to measure

35. At a point in space, the net gravitational field due to two masses is zero, but the gravitational potential there is not zero. This situation is possible because

36. If only Earth’s shape is considered, is smaller at the equator than at the poles because

37. A dimensional test is applied to . The dimension of must be

38. Early observations of planets were not enough by themselves to give a force law because they mainly described

39. The SI unit of gravitational potential is

40. At a point where gravitational potential is the same in a small surrounding region, the gravitational field there is

41. A satellite orbits a planet in a circle of radius . Its speed is increased by without changing its position. If the original circular speed is , the new total energy is

42. A planet has mass and radius . If Earth’s surface gravity is , the planet’s surface gravity is

43. Consider the statements below.
I. is the gravitational acceleration produced by Earth near its surface.
II. is equal to because both are constants.
III. near Earth can be written as .
The suitable option is

44. The following table compares two speeds at the same orbital radius around the same planet.

The correct comparison is

45. The constant for circular satellites around the same planet is

46. A satellite at radius has circular orbital speed , escape speed , and total circular-orbit energy . The correct set is

47. A body is at rest on Earth’s surface and then is placed in a circular orbit just above Earth’s surface. Ignoring air resistance and rotation, the total mechanical energy changes from

48. The binding energy of a satellite in a circular orbit of radius is

49. Kepler’s third law for a circular orbit can be derived by combining Newton’s gravitation with

50. Two spherical planets have the same uniform density. Planet has twice the radius of planet . The ratio of their surface gravities and escape speeds is