GRAVITATION
1. According to Newton's law of universal gravitation, the gravitational force between two objects is directly proportional to:
- a. The sum of their masses.
- b. The product of their masses.
- c. The inverse square of the distance between their centers.
- d. The cube of the distance between their centers.
2. The value of the universal gravitational constant (G) is approximately:
- a. 6.674 × 10^(-11) m/s^2
- b. 9.8 m/s^2
- c. 3 × 10^8 m/s
- d. 9.81 × 10^(-2) Nm^2/kg^2
3. The average density of the Earth is approximately:
- a. 1 g/cm^3
- b. 5 g/cm^3
- c. 10 g/cm^3
- d. 15 g/cm^3
4. The variation of the acceleration due to gravity (g) with altitude is primarily due to changes in:
- a. The mass of the Earth.
- b. The density of the Earth.
- c. The distance from the center of the Earth.
- d. The atmospheric pressure.
5. The variation of the acceleration due to gravity (g) with depth is primarily due to changes in:
- a. The mass of the Earth.
- b. The density of the Earth.
- c. The distance from the center of the Earth.
- d. The atmospheric pressure.
6. The weight of an object is:
- a. The force with which it is attracted by the Earth.
- b. The mass of the object multiplied by the acceleration due to gravity.
- c. The same as its mass.
- d. The force with which it attracts other objects.
7. The weight of an object on the surface of the Earth is maximum at:
- a. The North Pole.
- b. The South Pole.
- c. The equator.
- d. The weight is the same at all locations on the surface.
8. The weightlessness experienced by astronauts in space is due to:
- a. The absence of gravity in space.
- b. The cancellation of gravitational forces by other forces.
- c. The Earth's gravity being weaker in space.
- d. The motion of the spacecraft.
9. Artificial gravity can be created in a rotating spaceship by:
- a. Increasing the mass of the spaceship.
- b. Reducing the radius of the spaceship.
- c. Increasing the angular velocity of the spaceship.
- d. Decreasing the angular velocity of the spaceship.
10. The gravitational force between two objects will increase if:
- a. The mass of one object increases.
- b. The distance between the objects decreases.
- c. Both the mass of one object increases and the distance between the objects decreases.
- d. None of the above.
11. Which of the following statements is true about Newton's law of universal gravitation?
- a. It is only applicable on Earth.
- b. It only applies to objects in motion.
- c. It can be used to calculate the force between any two objects in the universe.
- d. It is only applicable to celestial bodies.
12. The value of 'g' is maximum at:
- a. The North Pole.
- b. The South Pole.
- c. The equator.
- d. The weight is the same at all locations on the surface.
13. Weightlessness in satellites is due to:
- a. The absence of gravity in space.
- b. The cancellation of gravitational forces by other forces.
- c. The Earth's gravity being weaker in space.
- d. The satellite's motion around the Earth.
14. The formula to calculate the weight of an object is:
- a. W = mg
- b. W = ma
- c. W = GMm/r^2
- d. W = F/m
15. The mass of an object can be determined by:
- a. Dividing the weight by the acceleration due to gravity.
- b. Dividing the weight by the mass of the Earth.
- c. Multiplying the weight by the acceleration due to gravity.
- d. Multiplying the weight by the mass of the Earth.
16. A satellite in a circular orbit around the Earth experiences:
- a. Weightlessness.
- b. No gravitational force.
- c. A constant acceleration.
- d. A varying acceleration.
17. The force of gravity acting on an object is:
- a. Independent of its mass.
- b. Dependent on its weight.
- c. Dependent on its volume.
- d. Dependent on its mass.
18. The weight of an object on the Moon is approximately:
- a. One-quarter of its weight on Earth.
- b. One-half of its weight on Earth.
- c. The same as its weight on Earth.
- d. Twice its weight on Earth.
19. The acceleration due to gravity is approximately:
- a. 9.8 m/s^2
- b. 6.674 × 10^(-11) m/s^2
- c. 3 × 10^8 m/s
- d. 9.81 × 10^(-2) Nm^2/kg^2
20. The concept of weightlessness is demonstrated in:
- a. An elevator moving upward.
- b. An elevator moving downward.
- c. A car accelerating forward.
- d. A car decelerating backward.
21. Which of the following quantities is NOT affected by gravity?
- a. Mass
- b. Weight
- c. Volume
- d. Density
22. The weight of an object is dependent on:
- a. The gravitational force acting on it.
- b. The surface area of the object.
- c. The speed of the object.
- d. The height of the object.
23. The acceleration due to gravity is approximately the same at all locations on Earth's surface because:
- a. The mass of the Earth is uniformly distributed.
- b. The Earth's atmosphere exerts a constant pressure.
- c. The Earth's rotation affects the gravitational force.
- d. The Earth's magnetic field influences gravity.
24. If the radius of the Earth were doubled while its mass remained the same, the acceleration due to gravity would be:
- a. Halved.
- b. Doubled.
- c. Quadrupled.
- d. Unchanged.
25. The value of 'g' is maximum at:
- a. The top of a mountain.
- b. Sea level.
- c. The center of the Earth.
- d. The North Pole.
26. The value of 'g' at the center of the Earth is:
- a. Zero.
- b. The same as at the Earth's surface.
- c. Infinite.
- d. None of the above.
27. The weight of an object on the surface of the Moon is approximately:
- a. One-sixth of its weight on Earth.
- b. One-third of its weight on Earth.
- c. The same as its weight on Earth.
- d. Twice its weight on Earth.
28. The weight of an object is maximum at:
- a. The North Pole.
- b. The South Pole.
- c. The equator.
- d. It is the same everywhere on Earth.
29. The force of gravity acting on an object is directly proportional to:
- a. The object's volume.
- b. The object's density.
- c. The object's mass.
- d. The object's weight.
30. The gravitational force between two objects is inversely proportional to:
- a. The sum of their masses.
- b. The product of their masses.
- c. The square of the distance between their centers.
- d. The cube of the distance between their centers.
31. The concept of weightlessness is observed when:
- a. The gravitational force on an object is balanced by the normal force.
- b. The gravitational force on an object is balanced by the frictional force.
- c. The gravitational force on an object is equal to zero.
- d. The gravitational force on an object is canceled by another force.
32. A satellite in a geostationary orbit is situated:
- a. Above the Earth's atmosphere.
- b. On the equator.
- c. At a fixed point above the Earth's surface.
- d. In a polar orbit.
33. The acceleration due to gravity at a height equal to the radius of the Earth is:
- a. One-fourth of the acceleration at the Earth's surface.
- b. Half of the acceleration at the Earth's surface.
- c. The same as the acceleration at the Earth's surface.
- d. Twice the acceleration at the Earth's surface.
34. The weight of an object at the Earth's surface is equal to the gravitational force exerted on it by:
- a. The Earth's core.
- b. The Earth's atmosphere.
- c. The Earth's mantle.
- d. The Earth as a whole.
35. Artificial gravity in a rotating spaceship is experienced due to:
- a. The increased mass of the spaceship.
- b. The increased weight of the spaceship.
- c. The centripetal force acting on objects inside the spaceship.
- d. The centrifugal force acting on objects inside the spaceship.
36. The weight of an object is measured using:
- a. A balance.
- b. A spring scale.
- c. A ruler.
- d. A stopwatch.
37. If the distance between two objects is doubled, the gravitational force between them will:
- a. Remain the same.
- b. Be halved.
- c. Be doubled.
- d. Quadruple.
38. The gravitational force between two objects is dependent on:
- a. The speed of the objects.
- b. The color of the objects.
- c. The surface area of the objects.
- d. The mass of the objects.
39. The acceleration due to gravity on Mars is approximately:
- a. The same as on Earth.
- b. One-tenth of the acceleration on Earth.
- c. Ten times the acceleration on Earth.
- d. Zero.
40. The weight of an object on the surface of Jupiter would be:
- a. Less than its weight on Earth.
- b. Greater than its weight on Earth.
- c. The same as its weight on Earth.
- d. Zero.
ANSWER KEY:
- c. The inverse square of the distance between their centers.
- a. 6.674 × 10^(-11) m/s^2
- b. 5 g/cm^3
- c. The distance from the center of the Earth.
- b. The density of the Earth.
- b. The mass of the object multiplied by the acceleration due to gravity.
- c. The equator.
- b. The cancellation of gravitational forces by other forces.
- c. Increasing the angular velocity of the spaceship.
- c. Both the mass of one object increases and the distance between the objects decreases.
- c. It can be used to calculate the force between any two objects in the universe.
- c. The equator.
- d. The satellite's motion around the Earth.
- a. W = mg
- a. Dividing the weight by the acceleration due to gravity.
- a. Weightlessness.
- d. Dependent on its mass.
- a. One-quarter of its weight on Earth.
- a. 9.8 m/s^2
- b. An elevator moving downward.
- c. Volume
- a. The gravitational force acting on it.
- a. The mass of the Earth is uniformly distributed.
- a. Halved.
- c. The center of the Earth.
- b. The same as at the Earth's surface.
- a. One-sixth of its weight on Earth.
- d. It is the same everywhere on Earth.
- c. The object's mass.
- c. The square of the distance between their centers.
- c. The gravitational force on an object is equal to zero.
- c. At a fixed point above the Earth's surface.
- c. The same as the acceleration at the Earth's surface.
- d. The Earth as a whole.
- c. The centripetal force acting on objects inside the spaceship.
- b. A spring scale.
- b. Be halved.
- d. The mass of the objects.
- b. One-tenth of the acceleration on Earth.
- b. Greater than its weight on Earth.
