Class 9 Science Chapter 9 Gravitation MCQ questions from the NCERT book. Here we have 10 exemplar MCQs in the end and 30 MCQs below.
We also have another page dedicated to Numericals for this chapter, with 24 questions. You might want to practice Physics Gravitation Solved Numerical Problems.
30 MCQ Questions for Class 9 Science: Chapter 9 Gravitation
Question 1. The universal law of gravitation states that every object in the universe attracts every other object with a force which is:
a) Directly proportional to the square of the distance between them
b) Inversely proportional to the product of their masses
c) Inversely proportional to the square of the distance between them
d) Directly proportional to the product of their masses
Answer:
c) Inversely proportional to the square of the distance between them
Question 2. What is the value of the universal gravitational constant (G)?
a) 6.673 × 10⁻¹¹ N m²/kg²
b) 9.8 m/s²
c) 6.674 × 10⁻¹⁰ N m²/kg²
d) 5.972 × 10²⁴ kg
Answer:
a) 6.673 × 10⁻¹¹ N m²/kg²
Question 3. The acceleration due to gravity ‘g’ is:
a) Same everywhere on the Earth
b) Different at different places on Earth
c) Dependent on the mass of the object
d) Always 9.8 m/s²
Answer:
b) Different at different places on Earth
Question 4. What is the weight of an object on the Moon compared to its weight on the Earth?
a) The same
b) Six times less
c) Six times more
d) Depends on the object’s mass
Answer:
b) Six times less
Question 5. If the distance between two objects is doubled, the gravitational force between them will:
a) Double
b) Become four times
c) Become half
d) Become one-fourth
Answer:
d) Become one-fourth
Question 6. The mass of an object is 60 kg on the Earth. What is its mass on the Moon?
a) 60 kg
b) 10 kg
c) 6 kg
d) 100 kg
Answer:
a) 60 kg
Question 7. What is the effect of altitude on the acceleration due to gravity?
a) It increases with altitude
b) It decreases with altitude
c) It remains constant
d) It first decreases then increases
Answer:
b) It decreases with altitude
Question 8. A satellite orbiting the Earth feels a gravitational force. This force is due to:
a) The Moon
b) The Sun
c) The Earth
d) The atmosphere
Answer:
c) The Earth
Question 9. The pressure exerted by an object on a surface is:
a) Directly proportional to area
b) Inversely proportional to area
c) Independent of the area
d) Dependent on the material of the object
Answer:
b) Inversely proportional to area
Question 10. If an object is partially immersed in a fluid, it experiences an upward force. This principle is known as:
a) Pascal’s Principle
b) Archimedes’ Principle
c) Newton’s Law of Gravitation
d) Boyle’s Law
Answer:
b) Archimedes’ Principle
Question 11. The buoyant force on an object immersed in a liquid depends on:
a) The mass of the object
b) The volume of the object
c) The density of the liquid
d) Both b and c
Answer:
d) Both b and c
Question 12. Archimedes’ Principle is used in designing:
a) Airplanes
b) Cars
c) Ships
d) Rockets
Answer:
c) Ships
Question 13. What causes buoyancy?
a) Density of an object greater than the fluid
b) Density of an object less than the fluid
c) Upward force exerted by the fluid
d) Gravitational pull of the earth
Answer:
c) Upward force exerted by the fluid
Question 14. Which of the following will float in water?
a) A substance with density greater than 1 g/cm³
b) A substance with density equal to 1 g/cm³
c) A substance with density less than 1 g/cm³
d) A substance with density much greater than 1 g/cm³
Answer:
c) A substance with density less than 1 g/cm³
Question 15. Why do objects weigh less in water?
a) Due to the surface tension of water
b) Due to the buoyant force of water
c) Due to the decrease in mass of the object
d) Due to the viscosity of water
Answer:
b) Due to the buoyant force of water
Question 16. The pressure exerted by a fluid at any point inside it is:
a) Same in all directions
b) Different in different directions
c) Only in the upward direction
d) Only in the downward direction
Answer:
a) Same in all directions
Question 17. The thrust on a surface is equal to:
a) Mass x Acceleration
b) Weight x Area
c) Weight / Area
d) Mass / Volume
Answer:
c) Weight / Area
Question 18. The SI unit of pressure is:
a) Pascal
b) Newton
c) Joule
d) Watt
Answer:
a) Pascal
Question 19. The weight of an object on the moon is:
a) Same as on Earth
b) Less than on Earth
c) More than on Earth
d) Zero
Answer:
b) Less than on Earth
Question 20. An object immersed in a fluid experiences an upward force. This principle is known as:
a) Pascal’s Law
b) Newton’s Law
c) Archimedes’ Principle
d) Bernoulli’s Principle
Answer:
c) Archimedes’ Principle
Question 21. The value of acceleration due to gravity (g) on the surface of the Earth is approximately __________ m/s².
Fill in the blank.
Answer:
9.8
Question 22. Objects with mass greater than the fluid in which they are immersed will __________.
Fill in the blank.
Answer:
Sink
Question 23. The pressure at a given depth in a liquid is __________ proportional to the depth.
Fill in the blank.
Answer:
Directly
Question 24. The force of attraction between two masses is called __________ force.
Fill in the blank.
Answer:
Gravitational
Question 25. The force that opposes the relative motion of objects in contact is known as __________.
Fill in the blank.
Answer:
Friction
Question 26. The gravitational force between two objects decreases as the distance between them increases. (True/False)
Answer:
True
Question 27. The weight of an object is the same on Earth and the Moon. (True/False)
Answer:
False
Question 28. An object will float in a fluid if its density is less than the density of the fluid. (True/False)
Answer:
True
Question 29. Pascal’s principle is used in hydraulic brakes. (True/False)
Answer:
True
Question 30. The center of mass of a body always lies within the material of the body. (True/False)
Answer:
False
Question on Match the Columns
Unmatched Columns – Questions
| Column A | Column B |
|---|---|
| (i) Universal Law of Gravitation | (a) Acceleration due to Earth’s gravity |
| (ii) Free Fall | (b) Weight is proportional to mass |
| (iii) Difference between Mass and Weight | (c) Upward force exerted by fluids |
| (iv) Buoyancy | (d) Mass constant, weight varies with gravity |
| (v) Acceleration due to Gravity (g) | (e) Force between two masses |
| (vi) Archimedes’ Principle | (f) Objects float or sink based on density |
Matched Columns – Answer
| Column A | Column B |
|---|---|
| (i) Universal Law of Gravitation | (e) Force between two masses |
| (ii) Free Fall | (a) Acceleration due to Earth’s gravity |
| (iii) Difference between Mass and Weight | (d) Mass constant, weight varies with gravity |
| (iv) Buoyancy | (c) Upward force exerted by fluids |
| (v) Acceleration due to Gravity (g) | (b) Weight is proportional to mass |
| (vi) Archimedes’ Principle | (f) Objects float or sink based on density |
MCQ questions from Exemplar Problems
Question 1. Two objects of different masses falling freely near the surface of moon would
a) have same velocities at any instant
b) have different accelerations
c) experience forces of same magnitude
d) undergo a change in their inertia
Answer:
a) have same velocities at any instant — Both fall with the same acceleration due to gravity on the moon, so at a given instant (starting together), their velocities are the same.
Question 2. The value of acceleration due to gravity
a) is same on equator and poles
b) is least on poles
c) is least on equator
d) increases from pole to equator
Answer:
c) is least on equator — g is minimum at the equator and maximum at the poles.
Question 3. The gravitational force between two objects is F. If masses of both objects are halved without changing distance between them, then the gravitational force would become
a) F/4
b) F/2
c) F
d) 2F
Answer:
a) F/4 — Since F ∝ m₁m₂, halving both masses makes (1/2) × (1/2) = 1/4 of the force.
Question 4. A boy is whirling a stone tied with a string in an horizontal circular path. If the string breaks, the stone
a) will continue to move in the circular path
b) will move along a straight line towards the centre of the circular path
c) will move along a straight line tangential to the circular path
d) will move along a straight line perpendicular to the circular path away from the boy
Answer:
c) will move along a straight line tangential to the circular path — Due to inertia, it continues in the direction of its instantaneous velocity.
Question 5. An object is put one by one in three liquids having different densities. The object floats with 1/2, 3/9 and 7/11 parts of their volumes outside the liquid surface in liquids of densities d1, d2 and d3 respectively. Which of the following statement is correct?
a) d1 > d2 > d3 a) d1 > d2 > d3 — More volume outside means liquid is denser (needs less submerged volume to balance weight). Outside fractions: 1/2 (largest), 3/9 = 1/3, 7/11 (smallest) ⇒ d1 highest, then d2, then d3.
b) d1 > d2 < d3
c) d1 < d2 > d3
d) d1 < d2 < d3
Answer:
Question 6. In the relation F = G M m/d², the quantity G
a) depends on the value of g at the place of observation
b) is used only when the earth is one of the two masses
c) is greatest at the surface of the earth
d) is universal constant of nature
Answer:
d) is universal constant of nature — G has the same value everywhere.
Question 7. Law of gravitation gives the gravitational force between
a) the earth and a point mass only
b) the earth and Sun only
c) any two bodies having some mass
d) two charged bodies only
Answer:
c) any two bodies having some mass
Question 8. The value of quantity G in the law of gravitation
a) depends on mass of earth only
b) depends on radius of earth only
c) depends on both mass and radius of earth
d) is independent of mass and radius of the earth
Answer:
d) is independent of mass and radius of the earth — G is a constant of nature.
Question 9. Two particles are placed at some distance. If the mass of each of the two particles is doubled, keeping the distance between them unchanged, the value of gravitational force between them will be
a) 1/4 times
b) 4 times
c) 1/2 times
d) unchanged
Answer:
b) 4 times — F ∝ m₁m₂, so doubling both masses gives 2 × 2 = 4 times.
Question 10. The atmosphere is held to the earth by
a) gravity
b) wind
c) clouds
d) earth’s magnetic field
Answer:
a) gravity