Q.1
From the top of twer of height 40 m a ball is projected upwards with a speed of 20m/s at an angle of elevation of 30°. Then the ratio of the total time taken by the ball to hit the ground to its time of flight ( time taken to come back to the same elevation ) is
  • a) 2 : 1
  • b) 3 : 1
  • c)3 : 2
  • d)4 : 1
Q.2
If the greatest range down an inclined plane is three times the greatest range up the plane, then the angle of inclination of the plane with the horizontal is
  • a) 75°
  • b) 45°
  • c) 60°
  • d) 30°
Q.3
If two stones projected from the same point with same initial speed but at angle π/3 and π/6 respectively have their ranges R1 and R2 then
  • a)R1=2R2
  • c)R1=5R2
  • d)R1=25R2
  • b) R₁=R₂
Q.4
The angle between the vector A and B is θ. The value of triple product A . B × A is
  • a) A2B
  • b) zero
  • c)A2Bsinθ
  • d)A2Bcosθ
Q.5
A projectile is projected in the upward direction making an angle of 60° with horizontal direction with a velocity of 147 m/sec. Then the time after which its inclination with the horizontal is 45° is
  • a) 15 sec
  • b) 10.98 sec
  • c)5.49 sec
  • d)2.745 sec
Q.6
The horizontal range of a projectile is 4√3 times its height, then the angle of projection is
  • a) 90°
  • b) 60°
  • c) 45°
  • d) 30°
Q.7
A player kicks up a ball at an angle θ to horizontal. The horizontal range is maximum when θ equals:
  • a)30°
  • b) 45°
  • c)60°
  • d)90°
Q.8
A body has an initial velocity of 3m/s and an acceleration of 1m/sec2 normal to the direction of initial velocity. Then the velocity of the body 4 sec after start is
  • a) 7 m/sec along initial velocity
  • b) 7 m/sec in the normal direction to initial velocity
  • c)7m/sec midway between initial and normal direction
  • d)5 m/sec at an angle of tan⁻¹ (4/3) with the direction of initial velocity
Q.9
An aeroplane is flying at height of 1960 m in horizontal direction with a velocity of 360 km/hr. When it is vertically above the point A on the ground, it drops a bomb . The bomb strikes at a point B on the ground. Then the time taken by the bomb to reach the ground is
  • a) 20√2 sec
  • b) 20 sec
  • c)10√2
  • d)10 sec
Q.10
A bomb is fired from a canon with velocity V m/sec at an angle θ with the horizontal direction. At the highest point of its path it explodes into two pieces of equal masses. One of the piece retraces its path, then the speed of the other piece immediately after explosion is
  • a) 3Vcosθ
  • b) 2Vcosθ
  • c) (3/2)Vcosθ
  • d) (√3/2) Vcosθ
Q.11
An arrow is shot air. Its range is 200 m and its time of flight is 5sec. IF g=10m/sec2, then the horizontal component of velocity of the arrow is:
  • a)12.5 m/sec
  • b) 25 m/sec
  • c)31.25 m /sec
  • d)40 m/sec
Q.12
Area of parallelogram formed by adjacent sides as the vectors A=3i + 2j and B=2j - 4k is
  • a) (√244) /2
  • b) √244
  • c)√122
  • d)(√122 )/ 2
Q.13
If A.B=AB then the angle between A and B is
  • a) 0°
  • b) 45°
  • c)90°
  • d)180°
Q.14
If A=4i- 2j + 6k and B=i -2j -3k, the angle which the A + B makes with x-axis is
  • a)
    ch-3_qn-200choice_img_no1.png
  • b)
    ch-3_qn-200choice_img_no2.png
  • c)
    ch-3_qn-200choice_img_no3.png
  • d)
    ch-3_qn-200choice_img_no4.png
Q.15
A particle is projected at an angle of 45° from a point lying 2m from the foot of a wall. It just touches the top of the wall and falls on the ground 4m from it. The height of the wall is
  • a) 3/4 m
  • b) 2/3 m
  • c)4/3 m
  • d)1/3 m
Q.16
The equation of projectile is y=√3 x - gx2 / 2, then angle of projection is
  • a) tanθ=1/√3
  • b) tanθ=√3
  • c)π/2
  • d)zero
Q.17
The equation of projectile is y=√3 x - gx2 / 2, the initial velocity is
  • a) 4 m/s
  • b) 2 m/s
  • c) 1 m/s
  • d) 5 m/s
Q.18
i×(j×k) is
  • a)i + j + k
  • b) i - j + k
  • c)zero vector
  • d)unit vector
Q.19
Many bullets are projected at equal angles with the horizontal in different directions with initial velocity v. The area in which these bullets are spread is
  • a) πv² / g
  • b) πv⁴/ g²
  • c)π2v4 / g²
  • d)π2v2 / g²
Q.20
The magnitude of the vector product of two vectors is √3 times their scalar product. The angle between the vectors is
  • a) π/2
  • b) π/6
  • c)π/3
  • d)π/4
Q.21
Which of the following statement is true
  • a) Energy, force and weight are vector quantities
  • b) Relative velocity, work and acceleration are vector quantities
  • c) displacement, force and electric field are vector quantities
  • d) Velocity, length and acceleration are vector quantities
Q.22
The component of 9i. +17k along z-axis has magnitude
  • a)zero
  • b) 17
  • c)9
  • d)26
Q.23
The magnitude of the resultant of two vectors is 12 units. If the magnitude of one vector is 20 units. what is the magnitude of the other vector? The resultant vector is at right angles to the "other vector"
  • a) 12 units
  • b) 16 units
  • c)18 units
  • d)28 unit
Q.24
A ball thrown by one player is caught by another after 2 seconds. the maximum height attained by the ball is nearly.
  • a) 2 m
  • b) 5 m
  • c)7 m
  • d)9 m
Q.25
If the range of projectile be R, then its K.E is maximum after covering ( from start) a distance equal to
  • a) R/4
  • b) R/2
  • c) 3R/4
  • d) R
Q.26
A person is moving in a circle of radius r with a constant speed v. The change in velocity in moving from a to B is
ch-3_que_no-213_img_no1.png
  • a)2vcos40
  • b) 2vsin40
  • c)2vcos20
  • d)2vsin20
Q.27
A blind person after walking 10 steps in one direction, each of length 80cm, turn randomly to by 90°. After walking a total of 40 steps, the maximum disparagement of the person from its starting point can be
  • a) 32 m
  • b) 16√2
  • c)8√2
  • d)0 m
Q.28
Resultant of two forces acting at right angles to each other is 1414 dyne. The magnitude of each force is
  • a)500 N
  • b) 100 N
  • c)1000 N
  • d)none of the above
Q.29
At what angle the two forces A+B and A-B acts so that their resultant is √(3A2 + B2)
  • a) π/6
  • b) π/3
  • c) π/2
  • d) π
Q.30
A vector x, when added to two vectors A=3i -5j + 7k and B=2i + 4j - 3k gives a unit vector along y axis. The vector x is
  • a)-5i + 2j - 4k
  • b) 5i + 2j - 4k
  • c)-5i - 2j + 4k
  • d)5i - 2j - 4k
0 h : 0 m : 1 s