NEET UG - Universal law of gravitation, acceleration due to gravity and its variation with altitude and depth Question Bank with Options

1. The acceleration due to gravity decreases with altitude because the distance from the center of the Earth increases, and the gravitational force is proportional to the inverse square of the distance. This statement is:

A) True for all altitudes

B) True only for altitudes much smaller than the Earth's radius

C) False, gravity increases with altitude

D) False, gravity is independent of distance

2. The universal law of gravitation implies that every particle of matter attracts every other particle with a force:

A) That depends on their temperature

B) That is proportional to the distance between them

C) That is proportional to the product of their masses and inversely proportional to the square of the distance between them

D) That is repulsive

3. If an object is brought from the surface of the Earth to a depth equal to the Earth's radius (i.e., the center), its acceleration due to gravity changes from g to:

A) g/2

B) 0

C) 2g

D) g

4. The term 'acceleration due to gravity' usually refers to its value at:

A) The center of the Earth

B) The poles

C) The equator

D) The Earth's surface

5. The variation in 'g' with latitude is mainly due to:

A) The Earth's non-spherical shape

B) The Earth's rotation

C) Altitude

D) The distribution of mass within the Earth

6. The reason why astronauts feel weightless in orbit is:

A) There is no gravity in space

B) They are in a state of continuous free fall

C) The Earth's gravitational pull is negligible at orbital altitudes

D) They have lost all their mass

7. The gravitational force exerted by the Earth on an object is its:

A) Mass

B) Inertia

C) Weight

D) Density

8. The acceleration due to gravity at a depth 'd' below the Earth's surface is g'' = g(1 - d/R). If d = R/2, then g'' is:

A) g/2

B) g

C) 3g/2

D) Zero

9. The acceleration due to gravity at height 'h' above the Earth (radius R) is g' = g (R/(R+h))^2. For very large heights (h >> R), g' approaches:

A) g

B) g/2

C) Zero

D) Infinite

10. If the Earth's mass increases by 10% and its radius decreases by 5%, what is the approximate percentage change in acceleration due to gravity on its surface?

A) 15% increase

B) 15% decrease

C) 20% increase

D) 5% increase

11. The decrease in acceleration due to gravity with depth is due to:

A) The reduction in the mass of the Earth above the point

B) The increase in the radius of the Earth

C) The increase in the gravitational constant

D) The decrease in the density of the Earth

12. Which of the following is a consequence of the variation of acceleration due to gravity with altitude?

A) Satellites can orbit the Earth

B) Objects weigh less at higher altitudes

C) Objects weigh more at higher altitudes

D) The Earth is spherical

13. The value of acceleration due to gravity is approximately 9.8 m/s^2 at:

A) The equator

B) The poles

C) Sea level

D) The center of the Earth

14. When an object falls freely under gravity, its acceleration is:

A) Zero

B) Dependent on its mass

C) Equal to the acceleration due to gravity at that location

D) Dependent on its velocity

15. The acceleration due to gravity on the surface of a planet is inversely proportional to:

A) Its mass

B) The square of its mass

C) Its radius

D) The square of its radius

16. The acceleration due to gravity on the surface of a planet is directly proportional to:

A) Its radius

B) The square of its radius

C) Its mass

D) The square root of its mass

17. The gravitational force between two objects is always:

A) Repulsive

B) Attractive

C) Both attractive and repulsive

D) Dependent on their velocity

18. If the Earth's radius were R and its mass M, the acceleration due to gravity on its surface is proportional to:

A) M/R

B) M/R^2

C) M^2/R

D) M/R^3

19. The formula g'' = g (1 - d/R) for acceleration due to gravity at depth 'd' implies that:

A) Gravity increases linearly with depth

B) Gravity decreases linearly with depth

C) Gravity decreases with the square of depth

D) Gravity remains constant with depth

20. The formula g' = g (1 - 2h/R) is an approximation for acceleration due to gravity at height 'h'. This approximation is valid when:

A) h is very large compared to R

B) h is comparable to R

C) h is very small compared to R

D) h is equal to R

21. As an object moves away from the Earth's center, its weight:

A) Increases

B) Decreases

C) Remains constant

D) Becomes zero

22. If an object weighs 100 N on Earth's surface, its mass is approximately:

A) 100 kg

B) 10.2 kg

C) 1000 kg

D) 1 kg

23. The weight of an object is:

A) Its mass multiplied by acceleration due to gravity

B) Its mass alone

C) Constant everywhere in the universe

D) Independent of gravity

24. The universal law of gravitation is a statement about the force between:

A) Charged particles

B) Magnetic poles

C) Any two objects with mass

D) Electrically neutral objects

25. What is the value of acceleration due to gravity at the Earth's center, assuming uniform density?

A) Zero

B) 9.8 m/s^2

C) g/2

D) Infinite

26. The effect of Earth's rotation on acceleration due to gravity is most pronounced at:

A) The poles

B) The equator

C) Mid-latitudes

D) The center of the Earth

27. If the Earth were to rotate faster, the apparent acceleration due to gravity at the equator would:

A) Increase

B) Decrease

C) Remain the same

D) Become zero

28. The formula g'' = g (1 - d/R) for acceleration due to gravity at depth 'd' is derived assuming:

A) The Earth is a hollow sphere

B) The Earth has uniform density throughout

C) The Earth's mass is concentrated at the surface

D) The density of the Earth increases with depth

29. The formula g' = g (R / (R + h))^2 for acceleration due to gravity at height 'h' is valid for:

A) All values of h

B) Only for h << R

C) Only for h >> R

D) When h is comparable to R

30. Which of the following statements is correct regarding the acceleration due to gravity?

A) It is constant everywhere on Earth

B) It is maximum at the equator and minimum at the poles

C) It is minimum at the equator and maximum at the poles

D) It is zero at the poles

31. The variation in acceleration due to gravity with depth is due to:

A) Change in the mass of the Earth above the point

B) Change in the radius of the Earth

C) Change in the gravitational constant G

D) Change in the object's weight

32. The variation in acceleration due to gravity with altitude is due to:

A) Change in mass of the Earth

B) Change in distance from the Earth's center

C) Change in the gravitational constant G

D) Change in the object's mass

33. If an object is taken from the surface of the Earth to a height equal to the Earth's radius, by what factor does the acceleration due to gravity change?

A) It remains the same

B) It becomes 1/4th

C) It becomes 1/2

D) It becomes 1/3rd

34. The acceleration due to gravity on the Moon is approximately 1/6th of that on Earth. This is primarily because:

A) The Moon has a smaller radius than Earth

B) The Moon has a smaller mass than Earth

C) The Moon has no atmosphere

D) The Moon is farther from the Sun than Earth

35. Which of the following factors does NOT affect the acceleration due to gravity on the surface of a planet?

A) Mass of the planet

B) Radius of the planet

C) Distance from the center of the planet

D) Mass of the object placed on the planet

36. At the center of the Earth (d=R), the acceleration due to gravity is:

A) Maximum

B) Minimum (zero)

C) Equal to g

D) Twice g

37. What is the formula for acceleration due to gravity at a depth 'd' below the Earth's surface?

A) g'' = g (R - d) / R

B) g'' = g (R + d) / R

C) g'' = g (R - d)^2 / R

D) g'' = g (R + d)^2 / R

38. The acceleration due to gravity at a depth 'd' below the Earth's surface is given by g'' = g (1 - d/R), for:

A) Any depth d

B) d << R

C) d >> R

D) d = R

39. As we go down from the surface of the Earth into a mine, the acceleration due to gravity:

A) Increases

B) Decreases

C) Remains constant

D) Becomes zero

40. What is the formula for acceleration due to gravity at a height 'h' above the Earth's surface, where R is the radius of the Earth?

A) g' = g (R / (R + h))^2

B) g' = g (R + h / R)^2

C) g' = g (R / (R - h))^2

D) g' = g (R - h / R)^2

41. As we go up from the surface of the Earth to a great height, the acceleration due to gravity:

A) Increases

B) Decreases

C) Remains constant

D) Becomes zero

42. The acceleration due to gravity at a height 'h' above the Earth's surface is given by g' = g (1 - 2h/R), for:

A) Any height h

B) h << R

C) h >> R

D) h = R

43. If the radius of the Earth were halved, keeping its mass constant, the acceleration due to gravity on its surface would:

A) Remain the same

B) Become half

C) Become double

D) Become four times

44. If the mass of the Earth were doubled, keeping its radius constant, the acceleration due to gravity on its surface would:

A) Remain the same

B) Become half

C) Become double

D) Become four times

45. The acceleration due to gravity 'g' depends on:

A) The mass of the object falling

B) The velocity of the object

C) The mass of the planet

D) The shape of the object

46. The acceleration due to gravity 'g' on the surface of the Earth is approximately:

A) 9.8 m/s^2

B) 6.67 x 10^-11 m/s^2

C) 1.62 m/s^2

D) 3.71 m/s^2

47. What is the approximate value of the universal gravitational constant G?

A) 6.67 x 10^-11 N m^2 / kg^2

B) 9.8 m/s^2

C) 1.38 x 10^-23 J/K

D) 8.31 J/(mol K)

48. The gravitational constant 'G' has the unit:

A) N m^2 / kg^2

B) N / kg^2

C) N m / kg

D) m^3 / (kg s^2)

49. Newton's universal law of gravitation states that the force of attraction between two point masses is inversely proportional to:

A) The product of their masses

B) The sum of their masses

C) The square of the distance between them

D) The distance between them

50. According to Newton's universal law of gravitation, the force of attraction between two point masses is directly proportional to:

A) The sum of their masses

B) The product of their masses

C) The difference of their masses

D) The square of the distance between them

Universal law of gravitation, acceleration due to gravity and its variation with altitude and depth - Question Bank