Very short answer type questions (1 mark each)
1. Name the force which keeps various planets and satellites moving in their orbits.
2. Write down the formula for the force of gravitation between two bodies having mass M1 and M2 when placed at a distance R from each other.
3. Which force is responsible for tides in the sea?
4. Why does a stone dropped from a certain height fall on the earth?
5. What is the SI unit of the acceleration due to gravity? What is its value on the surface of the earth?
6. What is meant by a free fall of a body?
7. What is the ratio of the acceleration due to gravity on the earth to that on the moon?
8. Define weight of a body. What are the units of weight?
9. Under what conditions does a body appear weightless?
10. State the universal law of gravitation.
Short answer type questions (2 marks each)
11. State Newton's universal law of gravitation.
12. Which of the two, 'g' and 'G' (a) is a vector?
(b) does not change with the location on the earth's surface?
13. The earth moves around the sun, but the sun does not revolve around the earth. Explain.
14. What happens to the weight of a person when he is
(a) at the top of a high mountain?
(b) deep inside the earth?
(c) at the centre of the earth?
15. Using Newton's law of gravitation, show that if the earth exerts equal force on the two bodies held near it, then their masses should be equal.
16. Mention two points of difference between mass and weight.
17. Show that the time taken by the two objects of different masses to fall through a certain height is equal.
Short answer type questions (3 marks each)
19. Mention three differences between 'g' and 'G'.
20. When will we see two objects moving towards each other due to the gravitational force of attraction between them?
21. Show that the acceleration of a body falling towards the earth is independent of the mass of the body.
22. When two objects in the two pans of a balance are such that the two pans remain stationary at the same height, why do we say that their masses are equal?
23. Differentiate between the mass and weight of a body.
Long answer type questions (5 marks each)
24. An apple falls towards the earth due to the gravitational force of attraction. The apple also attracts the earth with the same force. Why do we not see the earth rising towards the apple? Explain.
25. Describe the state of weightlessness with the help of a suitable example.
26. Show that the value of 'g' decreases as we go to higher altitudes above the surface of the earth. Mention one practical application of this property of g'.
1. Name the force which keeps various planets and satellites moving in their orbits.
2. Write down the formula for the force of gravitation between two bodies having mass M1 and M2 when placed at a distance R from each other.
3. Which force is responsible for tides in the sea?
4. Why does a stone dropped from a certain height fall on the earth?
5. What is the SI unit of the acceleration due to gravity? What is its value on the surface of the earth?
6. What is meant by a free fall of a body?
7. What is the ratio of the acceleration due to gravity on the earth to that on the moon?
8. Define weight of a body. What are the units of weight?
9. Under what conditions does a body appear weightless?
10. State the universal law of gravitation.
Short answer type questions (2 marks each)
11. State Newton's universal law of gravitation.
12. Which of the two, 'g' and 'G' (a) is a vector?
(b) does not change with the location on the earth's surface?
13. The earth moves around the sun, but the sun does not revolve around the earth. Explain.
14. What happens to the weight of a person when he is
(a) at the top of a high mountain?
(b) deep inside the earth?
(c) at the centre of the earth?
15. Using Newton's law of gravitation, show that if the earth exerts equal force on the two bodies held near it, then their masses should be equal.
16. Mention two points of difference between mass and weight.
17. Show that the time taken by the two objects of different masses to fall through a certain height is equal.
Short answer type questions (3 marks each)
19. Mention three differences between 'g' and 'G'.
20. When will we see two objects moving towards each other due to the gravitational force of attraction between them?
21. Show that the acceleration of a body falling towards the earth is independent of the mass of the body.
22. When two objects in the two pans of a balance are such that the two pans remain stationary at the same height, why do we say that their masses are equal?
23. Differentiate between the mass and weight of a body.
Long answer type questions (5 marks each)
24. An apple falls towards the earth due to the gravitational force of attraction. The apple also attracts the earth with the same force. Why do we not see the earth rising towards the apple? Explain.
25. Describe the state of weightlessness with the help of a suitable example.
26. Show that the value of 'g' decreases as we go to higher altitudes above the surface of the earth. Mention one practical application of this property of g'.
