| Class | 9th |
| Subject | Science |
| Chapter 9 | Gravitation |
| Question Type | Tick the Correct Answer |
| Download pdf File | Available |
Class 9 Science Work and Energy MCQ
Q.1. The Universal Law of Gravitation is important because:
(a) It explains the motion of objects in free fall
(b) It determines the weight of an object
(c) It explains the motion of planets around the Sun
(d) All of the above
Correct Answer: (d)
Q.2. Objects fall towards the Earth due to:
(a) Mass
(b) Weight
(c) Gravity
(d) Buoyancy
Correct Answer: (c)
Q.3. Gravitational force is a
(a) Long-range attractive force
(b) long-range repulsive force
(c) Short-range repulsive force
(d) Short-range attractive force
Correct Answer: (a)
Q.4. If we neglect the air resistance, the time taken by a freely falling body to reach the ground will not depend upon
(a) Height of free fall
(b) Acceleration due to gravity
(c) Mass of the body
(d) Speed with which body strikes the ground
Correct Answer: (c)
Q.5. 1 kg wt is equal to
(a) 9.8 N
(b) 980 N
(c) 98 N
(d) none of these
Correct Answer: (a)
Q.6. Purchasing 1 kilogram of sugar will be profitable at
(a) equator
(b) poles
(c) at 27 1/2°latitude
(d) 57 1/2°latitude
Correct Answer: (a)
Q.7. Reason of weightlessness in a satellite is
(a) Zero gravity
(b) No atmosphere
(c) Zero reaction force by satellite surface
(d) None of the above
Correct Answer: (c)
Q.8. The value of G
(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.
Correct Answer: (d)
Q.9. The force of attraction between two unit masses separated by a unit distance is called
(a) gravitational potential
(b) acceleration due to gravity
(c) gravitational field
(d) universal gravitational constant
Correct Answer: (d)
Q.10. When a body is thrown vertically upwards, acceleration due to gravity acting on it
(a) goes on decreasing
(b) remains constant
(c) goes on increasing
(d) none of the above
Correct Answer: (b)
Q.11. The atmosphere is held to the earth due to the
(a) moving winds
(b) force of gravity
(c) magnetic field of the earth
(d) rotation of earth
Correct Answer: (b)
Q.12. The weight of an object at the centre of the Earth is equal to
(a) infinite
(b) zero
(c) double the weight at the surface of the earth
(d) half the weight at the surface of the earth
Correct Answer: (b)
Q.13. When a stone falls from a tower towards the surface of earth
(a) only the Earth attracts the stone
(b) only the stone attracts the Earth.
(c) both the stone and the Earth attract each other.
(d) both the stone and the Earth repel each other.
Correct Answer: (c)
Q.14. The SI unit of pressure is
(a) Nm2
(b) Nm
(c) N/m3
(d) N/m2
Correct Answer: (d)
Q.15. An object weighs 10 N in air. When immersed fully in water, it weighs only 8 N. The weight of the liquid displaced by the object will be
(a) 2 N
(b) 8 N
(c) 10 N
(d) 12 N
Correct Answer: (a)
Q.16. 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 the gravitational force between them will be
(a) 1/4 times
(b) 4 times
(c) 1/2 times
(d) unchanged
Correct Answer: (b)
Q.17. If the gravitational force of attraction between the earth and a satellite revolving around it becomes zero, then the satellite will:
(a) continue to move in its orbit with same velocity
(b) move tangentially and escape away
(c) become stationary in its orbit
(d) None of the above
Correct Answer: (b)
Q.18. Which of the following units is used to measure
thrust? [NTSE 2013]
(a) Dyne
(b) Pascal
(c) Newton per metre square
(d) Dyne per centimetre
Correct Answer: (b)
Q.19. The weight of a rock on the moon is 200.6 N. What is its mass on the earth?
(Take g of earth = 9.8 ms–2, g of moon = 1.7 ms–2) [NTSE 2013]
(a) 20 kg
(b) 118 kg
(c) 200 kg
(d) 1180 kg
Correct Answer: (b)
Q.20. Which of the following statements are true? [NTSE 2013]
(i) The orbit of a planet is elliptical with the sun at one of its focus
(ii) The line joining the planet and the sun sweeps equal areas in equal intervals of time
(iii) The square of the mean distance of a planet from the sun is proportional to the cube of its orbital period
(a) Only (i) and (ii)
(b) Only (ii) and (iii)
(c) Only (i) and (iii)
(d) (i) and (ii)
Correct Answer: (a)
Q.21. Objects float or sink when placed on the surface of water due to:
(a) The object’s weight
(b) Buoyant force
(c) Density of the object
(d) All of the above
Correct Answer: (d)
Q.22. Weight is:
(a) The amount of matter in an object
(b) The force exerted on an object due to gravity
(c) The same as mass
(d) The force exerted on an object due to buoyancy
Correct Answer: (b)
| Chapter -1 Matter in Our Surroundings |
| Chapter – 2 Is Matter Around Us Pure? |
| Chapter -3 Atoms and Molecules |
| Chapter -4 Structure of the Atom |
| Chapter -5 The Fundamental Unit of Life |
| Chapter -6 Tissues |
| Chapter -7 Motion |
| Chapter -8 Force and Laws of Motion |
| Chapter -9 Gravitation |
| Chapter -10 Work and Energy |
| Chapter -11 Sound |
| Chapter -12 Improvement of Food Resources |