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Class 9 Science MCQ Questions of Gravitation with Answers?

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It’s a crucial chapter, therefore, you’ll need to develop in-depth learning of the Class 9 Science MCQ Questions of Gravitation with Answers. Students often confuse several terms included during this chapter. These MCQ Questions will act as a self-assessment for you once you’ve got studied the whole chapter.

To help you in exams your understanding, here could be a list of MCQ questions for class 9 Science. confirm you have got skilled these chapters earlier, and only then do you begin with this examination.

Practice MCQ Questions for class 9 Chapter-Wise

1. Two objects of different masses falling freely near the surface of the moon would

(a) have same velocities at any instant
(b) have different acceleration
(c) experience forces of the same magnitude
(d) undergo a change in their inertia

2. A boy is whirling a stone tied to a string in a 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 center 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

3. The atmosphere is held to the Earth by

(a) gravity
(b) wind
(c) clouds
(d) Earth’s magnetic field

4. 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

5. The acceleration due to gravity on the Earth depends upon the

(a) mass of the body
(b) mass of the Earth
(c) shape and size of the body
(d) volume of the body

6.  .......of a body is the quantity of matter contained in it.

(a) mass
(b) weight
(c) volume
(d) none of these

7. The earth and the moon are attracted to each other by gravitational force. The earth attracts the moon with a force that is:

(a) More than that exerted by the moon
(b) Same as that exerted by the moon
(c) Less than that exerted by the moon
(d) Not related to that exerted by the moon

8. An apple and a stone dropped from a certain height accelerates

(a) equally
(b) differently
(c) depending on density
(d) depends on the position of the Sun

9. The pressure exerted by man on earth is minimum when he

(a) sits
(b) stands on one foot
(c) stands on both feet
(d) lies on ground

10. When a body floats in a liquid, its apparent weight is always

(a) less than the weight of the body
(b) more than the weight of the body
(c) equal to the weight of the body
(d) zero

11. School bags have a broader base to reduce

(a) pressure
(b) weight
(c) air resistance
(d) normal reaction

12. The weight of an object is least in some region of the earth. What will be the color of bears found in that region?

(a) black
(b) white
(c) blue
(d) brown

13. SI Unit of pressure is

(a) Pascal
(b) Newton
(c) m/s
(d) Dyne

14. Density of a substance is defined as mass per unit ……………..

(a) weight
(b) volume
(c) time
(d) pressure

15. The relative density of a substance is the ratio of its density to that of 

(a) air
(b) water
(c) vacuum
(d) none of these

16. Weight of an object on the surface of the moon is

(a) 1/6 that on the surface of the earth
(b) 1/5 that on the surface of the earth
(c) 1/3 that on the surface of the earth
(d) 1/2 that on the surface of the earth

17. The atmosphere is held to the Earth by

(a) gravity
(b) wind
(c) clouds
(d) Earth’s magnetic field

18. For a given applied thrust, the pressure exerted on a surface by a sharp pin is

(a) more than the pressure exerted by a blunt pin
(b) less than the pressure exerted by a blunt pin
(c) equal to the pressure exerted by a blunt pin
(d) either less or equal to the pressure exerted by a blunt pin

19. Earth moves in a circular motion around the Sun because of ........... force,

(a) frictional
(b) static
(c) applied 
(d) gravitational 

20.  What is buoyant force-

(a) An upward force on an object immersed in a liquid
(b) Partially downward force
(c) A downward force on an object immersed in a liquid
(d) None of the above

See Answer below>

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Answer:

1. Answer : (a) have same velocities at any instant

Explanation: Objects of different masses falling freely near the surface of the moon would have the same velocities at any instant because they will have the same acceleration due to gravity.

2. Answer : (c) will move along a straight line tangential to the circular path

Explanation: The moment the string breaks the centripetal force acting towards the center ceases and hence no force acts on the system. So by Newton's first law of motion, the stone will continue in a straight line and will fly off along the tangent of the circular path.

3. Answer : (a) gravity

Explanation: The atmosphere is held around the Earth by gravity.

4. Answer :  (a) 2 N

Explanation: F = 10- 8

= 2N

5. Answer : (b) mass of the Earth

Explanation: The acceleration due to gravity depends upon the radius of the earth, a mass of the earth, and on a constant having unit Nm2/kg2.

6.  Answer : (a) mass

Explanation: The mass of a body is the quantity of matter it contains.

7. Answer :   (b) Same as that exerted by the moon

Explanation: According to the universal law of gravitation, two objects attract each other with equal force but in opposite directions. Therefore, the earth attracts the moon with the same force as the moon attracts the earth.

8. Answer : (a) equally

Explanation: The free fall of both objects will be the same. Both of them will fall due to the gravitational pull of the earth.

9. Answer :  (d) lies on the ground

Explanation: The pressure is inversely proportional to the area. As the area is maximum while lying down( unless the feet are incredibly large), therefore pressure will be minimum.

10. Answer : (d) zero

Explanation: The apparent weight of a floating object is zero.

11. Answer : (a) pressure

Explanation: School bags are provided with broad straps to increase the surface area in contact with the shoulders and reduce pressure on the shoulders. If thin straps would be used, then the surface area in contact with the shoulders would decrease which will lead to an increase in pressure on the shoulders.

12.Answer : (b) white

Explanation: Acceleration due to gravity is less in the case of poles and colour of bears found in these regions are white, called as a polar bear.

13. Answer :  (a) Pascal

Explanation:  The SI unit for pressure is the pascal (Pa), equal to one newton per square metre (N/m2, or kg·m-1·s−2).

14. Answer :  (b) volume

Explanation:  Density, the mass of a unit volume of a material substance. The formula for density is 

d = M/V,

15. Answer : (b) water

Explanation: The relative density of a substance is the ratio of its density to the density of water. A substance with a relative density less than 1 will float in water. For example, an ice cube, with a relative density of about 0.91, will float. A substance with a relative density greater than 1 will sink.

16. Answer :  (a) 1/6 that on the surface of the earth

Explanation: The moon's gravitation force is determined by the mass and the size of the moon. Hence, the weight of an object on the moon is 1/6th its weight on the earth.

17. Answer : (a) gravity

Explanation: The atmosphere is held around the Earth by gravity.

18. Answer :  (a) more than the pressure exerted by a blunt pin.

Explanation: For a given applied thrust, pressure exerted on a surface by a sharp pin is. more than the pressure exerted by a blunt pin.

19. Answer :  (d) gravitational 

Explanation: The earth moves around the sun because of the gravitational force of the sun on the earth. This force acts along the radius of the orbit of the earth towards ( or focus) its center.

20. Answer : (a) An upward force on an object immersed in a liquid

Explanation: Buoyant force is a force acting on an object opposite to gravity by fluid which is being submerged partially or completely in a fluid. It opposes the weight of an object. The buoyant force is given by volume displaced by an object into a density of fluid into gravitational acceleration.

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