CHAPTER :- KINEMATICS
(SECTION-A)
1. An athlete completes one round of a circular
track of radius R in 40 sec. What will be his displacement at
the end of 2 min. 20 sec
(A)
Zero (B)
2R
(C) 
(D)
2. A person travels along a straight road for
half the distance with velocity 
and the
remaining half distance with velocity 
The average
velocity is given by
(A) 
(B) 
(C) 
(D)
3. The displacement-time graph for two
particles A and B are straight lines inclined at angles of 
and 
with the time
axis. The ratio of velocities of 
is
(A) 
(B) 
(C) 
(D) 
4. Which of the following options is correct for
the object having a straight line motion represented by the following graph
(A) 3The
object moves with constantly increasing velocity from O to A and then it moves with constant velocity.
(B) Velocity
of the object increases uniformly
(C) Average velocity is zero
(D) The
graph shown is impossible
5. The displacement 
of a particle
along a straight line at time 
is given by 
. The acceleration of the particle is
(A) 
(B) 
(C) 
(D) 
6. The initial velocity of a body moving along a
straight line is 7 
. It has a uniform acceleration of 
. The distance covered by the body in the 5th
second of its motion is
(A) 25
m (B)
35 m
(C) 50
m (D)
85 m
7. A car moving with a speed of 40 km/h can be stopped by applying brakes after atleast 2 m. If the same car is moving with a
speed of 80 km/h, what is the
minimum stopping distance
(A) 8 m (B)
2 m
(C) 4 m
(D) 6 m
8. A body starts from rest. What is the ratio of the distance travelled by
the body during the 4th and 3rd second
(A) 
(B) 
(C) 
(D) 
9. If a car at rest accelerates uniformly to a
speed of 144 km/h in 20 s.
Then it covers a distance of
(A) 20
m (B)
400 m
(C)
1440 m (D)
2880 m
10. Equation of
displacement for any particle is 
. Its acceleration at time 
sec is
(A) 10 m/s2 (B) 16 m/s2
(C) 25 m/s2 (D)
32 m/s2
11. A particle moves along X-axis in such a way
that its coordinate X varies with time 
according to
the equation 
. The initial velocity of the particle is
(A) 
(B) 
(C) 
(D) 
12. A train of 150 meter length is going towards north direction at a speed of 
. A parrot flies at the speed of 
towards south
direction parallel to the railway track. The time taken by the parrot to cross
the train is
(A) 12 sec (B) 8 sec
(C) 15 sec (D) 10 sec
13. Two bodies of different masses 
and 
are dropped
from two different heights 
and 
. The ratio of the time taken by the two to cover
these distances are
(A) 
(B) 
(C) 
(D) 
14. A stone dropped from the top of the tower
touches the ground in 4 sec. The height of the tower is about
(A) 
(B) 
(C) 
(D) 
15. Two stones of different masses are dropped
simultaneously from the top of a building
(A) Smaller
stone hit the ground earlier
(B) Larger
stone hit the ground earlier
(C) Both
stones reach the ground simultaneously
(D) Which
of the stones reach the ground earlier depends on the composition of the stone
16. Water drops fall at regular intervals from a
tap which is 
above the
ground. The third drop is leaving the tap at the instant the first drop touches
the ground. How far above the ground is the second drop at that instant
(A) 2.50
m (B) 3.75 m
(C) 4.00
m (D) 1.25 m
17. A body starts to fall freely under gravity.
The distances covered by it in first, second and third second are in ratio
(A) 
(B) 
(C) 
(D) 
18. A ball of mass 
and another
ball of mass 
are dropped
from equal height. If time taken by the balls are 
and 
respectively,
then
(A) 
(B) 
(C) 
(D) 
19. Time taken by an object falling from
rest to cover the height of 
and 
is respectively
and then the ratio
of to is
(A) 
(B) 
(C) 
(D) 2h1 : h2
20. A particle is thrown vertically upwards.
If its velocity at half of the maximum height is 10 m/s, then maximum height attained by it is (Take 
m/s2)
(A) 8 m (B) 10 m
(C) 12 m (D) 16 m
21. Three different objects of masses 
and 
are allowed to
fall from rest and from the same point ‘O’
along three different frictionless paths. The speeds of the three objects, on
reaching the ground, will be in the ratio of
(A) 
(B) 
(C) 1 : 1 : 1
(D)
22. The position 
of a particle
varies with time as 
. The acceleration of the particle will be zero at
time equal to
(A) 
(B) 
(C) 
(D)
Zero
23. The variation of velocity of a particle with
time moving along a straight line is illustrated in the following figure.
The distance travelled by the particle in four seconds is
(A) 60 
(B) 55
(C) 25 (D)
30
24. The 
graph shown in
figure represents
(A) Constant
velocity
(B) Velocity
of the body is continuously changing
(C) Instantaneous
velocity
(D) The
body travels with constant speed upto time and then stops
25. Which of the following velocity-time graphs represent uniform motion
(A) 
(B) 
(C) 
(D) 
26. Assertion : Rocket in flight is not an illustration of projectile.
Reason : Rocket takes flight due to
combustion of fuel and does not move under the gravity effect alone.
(A)
If both assertion and reason are true and the reason is the correct explanation
of the assertion.
(B)
If both assertion and reason are true but reason is not the correct explanation
of the assertion.
(C)
If assertion is true but reason is false.
(D)
If the assertion and reason both are false.
27. A stone is just released from the window
of a train moving along a horizontal straight track. The stone will hit the
ground following
(A) Straight path
(B) Circular path
(C) Parabolic path
(D) Hyperbolic path
28. An aeroplane flying 490 m above ground level at 100 m/s, releases a block. How far on ground will it strike
(A) 0.1 km (B) 1 km
(C) 2
km (D) None
29. A particle (A) is dropped from a height and another particle (B) is thrown in horizontal direction
with speed of 5 m/sec from the same
height. The correct statement is
(A) Both particles will reach at
ground simultaneously
(B) Both particles will reach at
ground with same speed
(C) Particle (A) will reach at ground first with respect to particle (B)
(D) Particle (B) will reach at ground first with respect to particle (A)
30. A particle moves in a plane with constant
acceleration in a direction different from the initial velocity. The path of
the particle will be
(A) A
straight line
(B) An
arc of a circle
(C) A parabola
(D) An ellipse
31. A projectile fired with initial velocity
at some angle 
has a range 
. If the initial velocity be doubled at the same angle
of projection, then the range will be
(A) 
(B) 
(C) (D) 
32. In the motion of a projectile freely
under gravity, its
(A) Total energy is conserved
(B) Momentum is conserved
(C) Energy and momentum both are
conserved
(D) None is conserved
33. The range of a projectile for a given
initial velocity is maximum when the angle of projection is 
. The range will be minimum, if the angle of
projection is
(A) 
(B) 
(C) 
(D)
34. A ball thrown by one player reaches the
other in 2 sec. the maximum height attained by the ball above
the point of projection will be about
(A) 10 m (B) 7.5 m
(C) 5 m (D) 2.5 m
35. The height 
and the
distance along the
horizontal plane of a projectile on a certain planet (with no surrounding
atmosphere) are given by 
meter and 
meter, where is in second.
The velocity with which the projectile is projected is
(A) 8 m/sec
(B) 6 m/sec
(C) 10 m/sec
(D) Not obtainable from the data
(SECTION-B)
36. A projectile thrown with a speed 
at an angle has a range on the surface
of earth. For same and , its range on the surface of moon will be
(A) 
(B) 
(C) 
(D) 
37. The greatest height to which a man can
throw a stone is 
. The greatest distance to which he can throw it, will
be
(A) 
(B) (C) 
(D) 
38. The horizontal range is four times the
maximum height attained by a projectile. The angle of projection is
(A) 
(B) 
(C) 
(D) 
39. For a projectile, the ratio of maximum
height reached to the square of flight time is (g = 10 ms–2)
(A) 5 : 4 (B) 5 :
2
(C) 5 : 1 (D) 10
: 1
40. When a body is thrown with a velocity making an angle
with the
horizontal plane, the maximum distance covered by it in horizontal direction is
(A) 
(B) 
(C)
(D) 
41. Two bodies are projected with the same
velocity. If one is projected at an angle of 
and the other
at an angle of to the
horizontal, the ratio of the maximum heights reached is
(A) 3 : 1 (B) 1 :
3
(C)
1 : 2 (D) 2 : 1
42. If time of flight of a projectile is 10
seconds. Range is 500 meters. The
maximum height attained by it will be
(A) 125 m (B) 50 m
(C) 100 m (D) 150 m
43. If a body A of mass M is thrown
with velocity V at an angle of to the
horizontal and another body B of the
same mass is thrown with the same speed at an angle of to the
horizontal. The ratio of horizontal range of A to B will be
(A) 1 : 3 (B) 1 :
1
(C)
(D) 
44. Which of the following sets of factors
will affect the horizontal distance covered by an athlete in a long–jump event
(A) Speed before he jumps and his
weight
(B) The direction in which he leaps and
the initial speed
(C) The force with
which he pushes the ground and his speed
(D) None of these
45. In a projectile motion, velocity at maximum
height is
(A) 
(B) 
(C) 
(D) None of these
46. If two bodies are projected at 30o
and 60o respectively, with the same velocity, then
(A) Their ranges are same
(B) Their heights are same
(C) Their times of flight are same
(D) All of these
47. One car moving on a straight road covers one
third of the distance with 20 km/hr and
the rest with 60 km/hr. The average
speed is
(A) 40 km/hr (B) 80 km/hr
(C) 
km/hr (D)
36 km/hr
48. Which of the following is the graph
between the height (h) of a
projectile and time (t), when it is
projected from the ground
(A)
(B)
(C)
(D)
49. Assertion
: The
maximum horizontal range of projectile is proportional to square of velocity.
Reason
: The maximum horizontal range of projectile is equal to maximum height
attained by projectile.
(A) If both
assertion and reason are true and the reason is the correct explanation of the
assertion.
(B) If both assertion and reason are
true but reason is not the correct explanation of the assertion.
(C) If assertion is true but reason
is false.
(D) If the assertion and reason both
are false.
50. Match column I with
column II.
|
Column I (Physical quantity) |
Column II (Fermula) |
||
|
(A) |
Instantaneous veloctiy v = |
(p) |
|
|
(B) |
Average velocity, |
(q) |
|
|
(C) |
Instantaneous acceleration, a = |
(r) |
|
|
(D) |
Average acceleration, |
(s) |
|
(A)
A – p, B – q, C – r, D – s
(B)
A – r, B – s, C – p, D – q
(C)
A – s, B – p, C – q, D – r
(D)
A – q, B – r, C – s, D – p
CHAPTER
:- KINEMATICS
ANSWER KEY
1. (B) 2. (D) 3. (D) 4. (C) 5. (C) 6. (A) 7. (A)
8. (A) 9. (B) 10. (D) 11. (A) 12. (D) 13. (C) 14. (A)
15. (C) 16. (B) 17. (A) 18. (B) 19. (B) 20. (B) 21. (C)
22. (C) 23. (B) 24. (D) 25. (A) 26. (A) 27. (C) 28. (B)
29. (A) 30. (C) 31. (D) 32. (A) 33. (A) 34. (C) 35. (C)
36. (B) 37. (C) 38. (C) 39. (A) 40. (C) 41. (B) 42. (A)
43. (B) 44. (B) 45. (B) 46. (A) 47. (D) 48. (C) 49. (C)
50. (C)
SOLUTIONS
SECTION-A
1. (B)
Sol. Total time of motion is 2
min 20 sec = 140 sec.
As time period of
circular motion is 40 sec so in 140 sec.
athlete will complete 3.5 revolution i.e.,
He will be at diametrically opposite point i.e., Displacement = 2R.
2. (D)
Sol. As the total distance is divided into two equal
parts therefore distance averaged speed
3. (D)
Sol.
4. (C)
Sol. From given figure, it is clear that the net
displacement is zero. So average velocity will be zero.
5. (C)
Sol. Acceleration
6. (A)
Sol.
.
7. (A)
Sol. Þ
8. (A)
Sol.
because Hence
9. (B)
Sol. Here
Þ
10. (D)
Sol.
at
11. (A)
Sol. The velocity of the particle is
For initial velocity , hence .
12. (D)
Sol. Relative velocity
13. (C)
Sol.
14. (A)
Sol.
15. (C)
Sol. and h and g are same.
16. (B)
Sol. Time taken by first drop
to reach the ground
As the water drops fall at regular intervals from a tap therefore time
difference between any two drops
In this given time,
distance of second drop from the tap
Its distance from the
ground
17. (A)
Sol. ; when,
18. (B)
Sol. The time of fall is independent
of the mass.
19. (B)
Sol.
20. (B)
Sol. Let particle thrown with
velocity u and its maximum height is H then
When particle is at a height , then its speed is 10 m/s
From equation
Maximum height
21. (C)
Sol. (C) Speed of the object at reaching the
ground
If heights are equal
then velocity will also be equal.
22. (C)
Sol.
23. (B)
Sol. Distance = Area under v – t
graph
24. (D)
Sol. Up to time slope of the
graph is constant and after slope is zero i.e.
the body travel with constant speed up to time and then stops.
25. (A)
Sol. Slope of velocity-time
graph measures acceleration. For graph (A) slope is zero. Hence i.e. motion is uniform.
26. (A)
Sol. Motion of rocket is based on action reaction
phenomena and is governed by rate of fuel burning causing the change in
momentum of ejected gas.
27. (C)
Sol. Due to constant velocity along horizontal and
vertical downward force of gravity stone will hit the ground following
parabolic path.
28. (B)
Sol.
29. (A)
Sol. For
both cases constant.
30. (C)
31. (D)
Sol. . If initial velocity be doubled then range
will become four times.
32. (A)
Sol. An external force by gravity is present
throughout the motion so momentum will not be conserved.
33. (A)
Sol. Range; when , i.e. the body will fall at the point of
projection after completing one dimensional motion under gravity.
34. (C)
Sol. Þ
\
35. (C)
Sol. ,
at the time of projection i.e. and 
SECTION-B
36. (B)
Sol. Range is given by
On moon . Hence
37. (C)
Sol. For greatest height q = 90°
(given)
38. (C)
Sol. if R = 4H then
39. (A)
Sol. and
So
40. (C)
41. (B)
Sol. As\ =
42. (A)
Sol.
\
43. (B)
Sol. For complementary angles range
will be equal.
44. (B)
Sol. RangeIt is clear that range is proportional to the
direction (angle) and the initial speed.
45. (B)
Sol. Only horizontal component of velocity .
46. (A)
Sol. For complementary angles
range is same.
47. (D)
Sol.
Average speed
48. (C)
Sol.
\
\
49. (C)
Sol. \when \
Height Þ when
It is clear that 
50. (C)
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