Q.1
Two like parallel forces P and 3P are 40cm apart. If the directions of P is reversed, then their resultant shifts through a distance .. [ Roorkee 1998]
  • a) 30 cm
  • b) 40 cm
  • c)50 cm
  • d)60 cm
Q.2
Two balls are projected making an angle of 30° and 45° respectively with the horizontal. if both have same velocity at the highest points of their path, then the ratio of their velocities of projection is [ C.S.E.P 2001]
  • a) √3 : √2
  • b) √2 : 1
  • c) √2 : √ 3
  • d) √3 : 2
Q.3
If a stone is to hit at a point which is at a distance d away and at a height h above the point from where the stone starts, then what is the value of initial speed u if stone is launched at an angle θ [ Hariyana C.E.T 2002]
  • a)
    ch-3_qn-125choice_img_no1.png
  • b)
    ch-3_qn-125choice_img_no2.png
  • c)
    ch-3_qn-125choice_img_no3.png
  • d)
    ch-3_qn-125choice_img_no4.png
Q.4
Let F be the force acting on a particle having position vector r and T be the torque of this force about the origin . Then.. [ AIEEE2003]
  • a) r⋅T=0 and F⋅T ≠ 0
  • b) r⋅T ≠ 0 and F ⋅ T=0
  • c)r⋅T ≠ 0 and F⋅T ≠ 0
  • d)r⋅T=0 and F⋅T=0
Q.5
Three forces start acting simultaneously on a particle moving with velocity. These forces are represented in magnitude and direction by three sides of triangle as shown in figure. The particle will move with velocity
ch-3_que_no-127_img_no1.png
  • a) less than v
  • b) greater than v
  • c)|v| in the direction of the largest force
  • d)v remains unchanged
Q.6
A block is dragged on a smooth plane with the help of a rope which moves with velocity v as shown in figure. The horizontal velocity of the block is
ch-3_que_no-128_img_no1.png
  • a) v
  • b) vsinθ
  • c) v/sinθ
  • d) v/cosθ
Q.7
A body is projected at time t=0 from a certain point on a planet surface with a certain velocity at a certain angle with the planet,s surface ( assumed horizontal ). The horizontal and vertical displacement x and y (in meters) respectively vary with time t (in second) as x=10t√3 and y=10t-tWhat is the magnitude and direction of the velocity with which the body is projected?
  • a)20m/s at an angle of 30° with the horizontal
  • b)20m/s at an angle of 60° with the horizontal
  • c)10m/s at an angle of 30° with the horizontal
  • d)10m/s at an angle of 60° with the horizontal
Q.8
The area of the parallelogram formed from the vectorsA=i -2j + 3k and B=3i - 2j + k as adjacent sides is
  • a) 4√3
  • b) 4√6
  • c)8√3
  • d)8√6
Q.9
The angle between A and B is θ. R=A + B makes an angle θ/2 with A. Which of the following is true?
  • a) A=2B
  • b) 2A=B
  • c) AB=1
  • d) none of the above
Q.10
A particle is projected from a point O with velocity u in a direction making an angle α upward with the horizontal. At P, it is moving at right angle to its initial direction of projection, its velocity at P is ..
  • a)u tanα
  • b) ucotα
  • c)ucosecα
  • d)usecα
Q.11
The velocity of a particle P moving freely under gravity is 4.9 m/s, the direction being 30° with the downward normal
  • a) its acceleration normal to the direction of motion at P=9.8 m/s2
  • b) the radius of curvature of P of the parabolic trajectory of particle is 4.9m
  • c)the particle has no acceleration normal to the direction of motion
  • d)the radius of curvature at P of the path depends upon the initial velocity of projection
Q.12
A particle is projected up an inclined as shown in figure. For maximum range over the inclined plane the value of θ should be
ch-3_que_no-135_img_no1.png
  • a) 45°
  • b) 15°
  • c)30°
  • d)60°
Q.13
A particle located at x=0 at time t=0, starts moving along with the positive x-direction with velocity 'v' that varies as v=α√x. The displacement of the particle varies with time as [ AIEEE 2006]
  • a)t2
  • b) t
  • c)√t
  • d)t3
Q.14
A particle is projected at 60° to the horizontal with a kinetic energy K. The kinetic energy at the highest point is [ AIEEE 2007]
  • a) K/2
  • b) K
  • c)zero
  • d)K/4
Q.15
The velocity of a particle is v=vo +gt + ftIf its position is x=0 at t=0, then its displacement after unit time (t=1) is [ AIEEE 2007]
  • a) vo + g/2 + f
  • b) vo + 2g + 3f
  • c)vo + g/2 + f/3
  • d)vo + g + f
Q.16
A particle has an initial velocity of 3i + 4j and an acceleration of 0.4i+0.3j . Its speed after 10s is [ AIEEE 2009]
  • a) 7√2 units
  • b) 7 units
  • c) 8.5 units
  • d) 10 units
Q.17
If the magnitudes of A, B and C are 12, 5 and 13 units respectively and A + B=C, then the angle between A and B is
  • a)0
  • b) π
  • c)π/2
  • d)π/4
Q.18
If A=B + C and the magnitude of A, B and C are 5,4,3 units, the angle between A and C is .. [ CBSE 1990]
  • c)π/2
  • a) cos⁻¹ (3/5)
  • b) cos⁻¹(4/5)
  • d)sin⁻¹(3/4)
Q.19
Out of the following sets of forces, the resultant of which cannot be zero [ CPMT 1985]
  • a) 10,10,10
  • b) 10,20,40
  • c)10,10,20
  • d)10,20,20
Q.20
Out of following pairs, the resultant of which cannot be 4 Newton [ CPMT 1985]
  • a) 2N and 2N
  • b) 2N and 6 N
  • c) 2N and 4N
  • d) 2N and 8N
Q.21
A person moves 30 m North, then 20m East then 30√2 m South-West. His displacement from the original position is [ CPMT 1989]
  • a)15 m East
  • b) 28 m South
  • c)10 m West
  • d)14 m South-West
Q.22
The length of seconds hand of watch is 1cm. the change in velocity of its tip in 15 seconds is [ MPPMT 1987]
  • a) zero
  • b) π/ (30√2) cm/sec
  • c)(π/30) cm/sec
  • d)2π/(30√2) cm/sec
Q.23
Consider a F=4 i - 3 j. Another vector perpendicular to F is ..[ MPPMT 1987]
  • a) 4i+3j
  • b) 6i
  • c)7k
  • d)3i - 4j
Q.24
Consider a F1=4 i + 5 k and F2=3 j - 4 k. The magnitude of the scalar product of these vector is [ MPPMT 1987]
  • a) 20
  • b) 23
  • c) 5√(33)
  • d) 26
Q.25
A river is flowing from west to east at a speed of 5m/min. A man on the south bank of the river, capable of swimming at 10 m/min in still water, wants to swim across the river in shortest time. He should swim in a direction
  • a)due north
  • b) 30° east of north
  • c)30° west of north
  • d)60° east of north
Q.26
A particle is moving eastwards with velocity of 5m/sec. In 10 sec the velocity changes to 5m/sec north-wards. the average acceleration in this time is [ CPMT 1998]
  • a) zero
  • b) (1/√2) m/sec2 towards north-west
  • c)30° west of north
  • d)60° east of north
Q.27
The magnitude of a given vectors with end points (4, - 4, 0) and (-2, - 2, 0) must be
  • a) 6
  • b) 5√2
  • c)4
  • d)2√10
Q.28
Choose the wrong statement
  • a) Three vectors of different magnitudes may be combined to give zero resultant
  • b) Two vectors of different magnitudes can be combined to give a zero resultant
  • c) The product of a scalar and vector is a vector quantity
  • d) All above statements are wrong statement
Q.29
A boat is sent across a river with velocity of 8km/h. If the resultant velocity of the boat is 10km/h, the river is flowing with velocity of [ CBSE 1994]
  • a)12.8 km/hr
  • b) 6 km/hr
  • c)8 km/hr
  • d)10 km/hr
Q.30
The angle between vectors ( A×B) and (B×A) is
  • a) zero
  • b) π
  • c)π/4
  • d)π/2
0 h : 0 m : 1 s