Physics XI Karachi Board Fill in the Blanks - Chapter 6

Chapter 6 - Gravitation
1. According to the law of gravitation, every body in the universe attracts every other body with a force that is directly proportional to the __________ and inversely proportional to the square of the distance between their centres.

2. If the distance between two bodies is doubled, the gravitational force between them decreases to __________ of its former value.

3. If the distance between two bodies is halved, the force of attraction between them increases to __________ its former value.

4. The acceleration due to gravity is inversely proportional to the __________ of the distance from centre of earth.

5. The force of attraction, which the earth exerts on a body, is called __________.

6. Spring balance is used to determine __________ of a body.

7. The point of body at which whole weight of the body seems to act is called __________.

8. If the force acting on a body is equal to its weight then the acceleration produced in the body is equal to __________.

9. The centre of gravity of a body of rectangular shape is the point where its __________ intersect each other.

10. __________ is the centre of solar system.

11. The distance from the centre of the earth to the centre of the moon is called __________.

12. The time taken by the earth to complete one revolution around the sun is __________.

13. The direction of weight is always toward the centre of the __________.

14. Newton made the hypothesis that every body in the universe __________ the other body.

15. The moon is freely falling to __________.

16. The time taken by the moon to complete one revolution around the earth is __________.

17. The acceleration of the moon is __________.

18. The moon’s orbit is about __________.

19. Acceleration due to gravity decreases at __________ rate for a point above the surface of earth then for the same point below the surface of the earth.

20. Weight of a body is a __________ quantity.

21. The __________ is responsible for the motion of the planets around the sun.

22. Artificial gravity is produced in a satellite by spinning its own __________.

23. The value of ‘g’ is inversely proportional to the __________ of the radius of the earth.

24. If the mass of earth becomes four times then the value of ‘g’ will be __________.

25. The acceleration due to gravity on moon is __________ the acceleration due to gravity on the surface of the earth.

26. Acceleration due to gravity at the centre of the earth is __________.

27. The weight of a body at the pole is __________ than at equator.

28. The gravitational pull at equator is __________ than at poles.

29. The force required to prevent a body from falling or accelerating in a frame of reference is called the __________ of the body.

30. An astronaut in a satellite orbiting around the earth experiences a state of __________ because the satellite orbiting with a centripetal acceleration equal to ‘g’.

31. Artificial gravity is produced in the satellite to overcome the __________ in the satellite.

32. Artificial gravity is produced in the satellite by __________ it about its own axis.

33. The value of the average density of the earth is __________ kg/m3.

34. The dimension of gravitation constant is __________.

35. The expression for the frequency of rotation of the satellite to produce artificial gravity is __________.