Kumar from a metal
1. The retardation of a particle moving in a straight line is proportional to its displacement
(proportionality constant being unity). Initial velocity of the particle is v
0
. Find the total
displacement of the particle till it comes to rest.
(a)
2
0
v
(b) v
0
(c)
3
0
v
(d)
4
2
0
v
2. A bullet is fired with a gun from a tower horizontally with a velocity 400 m/s. At the
same time a stone is dropped from the same tower
(a) the stone will reach the ground first
(b) the bullet will reach the ground first
(c) both will reach the ground at the same time
(d) (a) and (b) according to the height of tower
3. A particle starts moving from the position of rest under a constant acceleration. It travels
a distance x in the first 10 sec and distance y in the next 10 sec, then
(a) y = x (b) y = 2x (c) y = 3x (d) y = 4x
4. The velocity of a body depends on time according to the equation v = 20 + 0.1t
2
. The
body is undergoing
(a) uniform acceleration (b) uniform retardation
(c) non-uniform acceleration (d) zero acceleration
6. A 150 m long train is moving to north at a speed of 10 m/s. A parrot is flying towards
south with a speed of 5 m/s crosses the train. The time taken by the parrot to cross the
train would be
(a) 30 s (b) 15 s (c) 8 s (d) 10 s
7. What is the average velocity during
time interval t = 2 s to t = 5 s, in the
following position time curve?
(a) 2 m/s
(b) 2/3 m/s
(c) 1.2 m/s
(d) 0.4 m/s
1
2
3
4
5
2
4
6
x(m)
t(s)
P
Q
8. A particle is projected with a velocity u, at an angle , with the horizontal. Time at
which its vertical component of velocity becomes half of its net speed at the highest
point will be
(a)
g
u
2
(b)
( )
− cossin
2g
u
(c)
( )
− sincos2
2g
u
(d)
( )
− cossin2
2g
u
9. The velocity-time graph of a particle moving
along a straight line is as shown in figure.
Calculate the distance covered between t = 0 to
t = 10 seconds.
(a) 10 m (b) 20 m
(c) 60 m (d) 50 m
t (s)
O
5
v (m/s)
4
10
10. The graph given shows the velocity v versus time t
for a body. Which of the following graphs shown
represents the corresponding acceleration versus
time graphs?
t
v
(a)
t
a
(b)
t
a
(c)
a
t
(d)
t
a
11. For position-time(x-t) curve as shown in
figure, the velocity-time (v-t) curve will be
x
t
1
t
2
t
3
t
4
t
5
t
(a)
v
t
1
t
2
t
3
t
4
t
5
t
(b)
v
t
1
t
2
t
3
t
4
t
5
t
(c)
v
t
1
t
2
t
3
t
4
t
5
t
(d)
v
t
1
t
2
t
3
t
4
t
5
t
12. The position of a particle is given by
kjtitr
ˆ
4
ˆ
3
ˆ
3
2
−+=
, where t is in seconds and
r
is meters. Find out magnitude and direction of velocity
v
with horizontal at
s3=t
.
(a)
)2(tanm/s,53
1−
=
(b)
=
−
3
2
tanm/s,53
1
(c)
)3(tanm/s,23
1−
=
(d)
=
−
2
1
tanm/s,53
1
13. The position of an object moving along x-axis is given by
3
3
++= btatx
, where x is
in metres and t in seconds. If velocity at t = 1 s and t = 4 s is 0.3 m/s and 27.3 m/s
respectively, the value of a and b will be
(a) 0.6 m/s
3
, +1.5 m/s (b) 0.6 m/s
3
, –1.5 m/s
(c) 1.6 m/s
3
, –1.5 m/s (d) none of these
14. The initial velocity of a body moving along a straight line is 7 m/s. It has a uniform
acceleration of 4m/s
2
. The distance covered by the body in the 5
th
second of its motion
is
(a) 25 m (b) 35 m (c) 50 m (d) 85 m
15. The velocity time graph of a particle starting
from rest from a point P is shown here. Particle
will reach P again, after staring from P in time
(a) 8s (b) 10s
(c) 12s (d) 16s
6
2
4
v (m/s)
P
8
t (s)
16. The velocity of a particle moving along the x–axis is given by v = x
3
– 6x
2
+ 12 where
v is in m/s and x is in m. Acceleration of the particle when it is passing through the point
x = 4 m will be
(a) – 20 ms
–2
(b) – 10 ms
–2
(c) – 5 ms
–2
(d) zero
17. A particle located at x = 0 at time t = 0, starts moving along the positive x-direction
with a velocity ‘v’ that varies as
xv =
. The displacement of the particle varies with
time as
(a) t
3
(b) t
2
(c) t (d) t
1/2
18. Position-time curve of a body moving along a
straight line is shown in figure. The velocity-time
curve for the motion of the particle will be
t
x
(a)
t
v
(b)
t
v
(c)
t
v
(d)
t
v
19. The position vector
r
of a moving particle at time t after the start of the motion is given
by
End of Document
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