## GRAVITATION

credits: Dennis Nilson |

*MCQs***Q1: An object moving in (upward) direction opposite to the gravitational force of earth performs _________**

(a) accelerated motion

(b) motion with constant velocity

(c) oscillations

(d) retarded motion

**Q2: The value of acceleration due to gravity of the surface of the earth is**

(a) 2 m/s2

(b) 4.9 m/s2

(c) 9.8 m/s2

(d) 8 m/s2

**Q3: The mass of an object __________**

(a) varies at different locations

(b) remains constant

(c) can be measured using spring balance

(d) is in the direction of gravitational force.

**Q4: The value of acceleration due to gravity at the poles**

(a) Is more than at the equator

(b) Same as at the equator

(c) Is less than at the equator

(d) zero

**Q5: When an object is released freely from certain height without applying any external force, then the object**

(a) will move upwards with accelerated motion

(b) will move downwards with accelerated motion

(c) will move downwards with constant velocity

(d) will move upwards with constant velocity

**Q6: The gravitational force between two bodies is**

(a) always repulsive

(b) always attractive

(c) can be attactive or repulsive

(d) neutral

**Q7: Weight of an object on the surface of the moon is**

(a) 1/5 th that on the surface of the earth

(b) 1/3 that on the surface of the earth

(c) ½ that on the surface of the earth

(d) 1/6 that on the surface of the earth

**Q8: The force of attraction between two bodies (each having mass of 1kg) are kept at a distance of 1m w.r.t. each other is:**

(a) 9.8 N

(b) 6.7 N

(c) 980 N

(d) 6.7 x 10 -11 N

**Q9: The time of ascent when measured from the point of projection of a body projected upwards, the**

(a) Time of ascent > Time of descent

(b) Time of ascent = Time of descent

(c) Time of ascent < Time of descent

(d) All of these

**Q10: The relative density ___________**

(a) has unit of kg/m3

(b) has unit of g/cm3

(c) has unit of kg/m2

(d) is unitless

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Answers:

1: (d) retarded motion

2: (c) 9.8 m/s2

3: (b) remains constant

4: (a) Is more than at the equator

5: (b) will move downwards with accelerated motion

6: (b) always attractive

7: (d) 1/6 that on the surface of the earth

8: (d) 6.7 x 10 -11 N

9: (b) Time of ascent = Time of descent

10:(d) is unitless