1000+ Applied Mechanics and Graphic Statics Multiple Choice Question Answer [Solved]

1. The unit of impulse, is
A. kg.m/sec
B. kg.m/sec
C. kg.m/sec²
D. kg.m/sec
Answer : A

2. The centre of gravity of a quadrant of a circle lies along its central radius at a distance of
A. 0.2 R
B. 0.4 R
C. 0.3 R
D. 0.6 R
Answer : D

3. The angle of friction is:
A. The ratio of the friction and the normal reaction
B. The force of friction when the body is in motion
C. The angle between the normal reaction and the resultant of normal reaction and limiting friction
D. The force of friction at which the body is just about to move
Answer : C

4. The shape of a suspended cable for a uniformly distributed load over it is
A. Circular
B. Parabolic
C. Catenary
D. Cubic parabola
Answer : B

5. For a simple pendulum, time period for a beat, is
A. ? ?(l/g)
B. ? ?(2l/g)
C. ? ?(g/2l)
D. ? ?(l/2g)
Answer : A

6. A particle moves with a velocity of 2 m/sec in a straight line with a negative acceleration of 0.1 m/sec2. Time required to traverse a distance of 1.5 m, is
A. 40 sec
B. 30 sec
C. 20 sec
D. 15 sec
Answer : C

7. If l is the span of a light suspension bridge whos each cable carries total weight (w) and the central dip is y, the horizontal pull at each support, is
A. wl/4y
B. wl/8y
C. wl/2y
D. wl
Answer : B

8. When two forces, each equal to P, act at 90° to each other, then the resultant will be
A. P
B. P?2
C. P/?2
D. 2P
Answer : B

9. The ratio of the moment of inertia of a rectangle about its centroidal axis to the moment of inertia about its base, is
A. 1/4
B. 1/2
C. 3/4
D. 2
Answer : A

10. A rod AB carries three loads of 30 N, 70 N and 100 N at distances of 20 mm, 90 mm and 150 mm respectively from A. Neglecting the weight of the rod, the point at which the rod will balance is
A. 109.5 mm from A
B. 119.5 mm from A
C. 125.5 mm from A
D. 132.5 mm from A
Answer : A

11. The potential energy of a particle falling through a straight shaft drilled through the earth (assumed homogenous and spherical) is proportional to
A. log r
B. r
C. r²
D. 1/r Where r is the distance of the particle from centre of the earth
Answer : C

12. The reaction at the support A of the beam shown in below figure is
A. 2 t
B. 5.8 t
C. 0.2 t
D. 3.5 t
Answer : A

13. If two bodies of masses M₁ and M₂(M₁ > M₂) are connected by alight inextensible string passing over a smooth pulley, the tension in the string, will be given by
A. T = g(M₁ - M₂)/(M₁ + M₂)
B. T = g(M₁ + M₂)/(M₁ × M₂)
C. T = g(M₂ - M₁)/(M₁ + M₂)
D. T = g(M₂ + M₁)/(M₂ - M₁)
Answer : A

14. Energy may be defined as
A. Power of doing work
B. Capacity of doing work
C. Rate of doing work
D. All the above
Answer : B

15. In a simple screw jack, the pitch of the screw is 9 mm and length of the handle operating the screw is 45 cm. The velocity ratio of the system is
A. 1.5
B. 5
C. 25
D. 314
Answer : D

16. The C.G. of the shaded area of the below figure whose curve OM is a parabola from y-axis, is
A. a/4
B. 3a/4
C. 3b/10
D. 3a/10
Answer : B

17. The instantaneous centre of a member lies at the point of intersection of two lines drawn at the ends of the member such that the lines are inclined to the direction of motion of the ends at
A. 30°
B. 45°
C. 60°
D. 90°
Answer : D

18. A projectile is fired with a velocity of 100.3 m/sec. at an elevation of 60°. The velocity attained by the projectile when it is moving at a height of 100 m, is
A. 70 m/sec
B. 75 m/sec
C. 80 m/sec
D. 90 m/sec
Answer : D

19. A ladder of weight 'w' rests against a smooth vertical wall, and rests on rough horizontal ground, the coefficient of friction between the ladder and the ground being 1/4. The maximum angle of inclination of the ladder to the vertical, if a man of weight 'w' is to walk to the top of it safely, is tan'1 x, where x is
A. 1/4
B. 1/3
C. 3
D. 4
Answer : B

20. Newton's law of Collision of elastic bodies states that when two moving bodies collide each other, their velocity of separation
A. Is directly proportional to their velocity of approach
B. Is inversely proportional to their velocity ofapproach
C. Bears a constant ratio to their velocity of approach
D. Is equal to the sum of their velocities of approach
Answer : C

21. A weight W is suspended at the free end of a light member hinged to a vertical wall. If the angle of inclination of the member with the upper wall is ?°, the force introduced in the member, is
A. W sec ?
B. W cos ?
C. W sin ?
D. W cosec ?
Answer : A

22. The rotational velocity of a satellite is increased by 450 m per second if its launch is done from equator
A. Eastward
B. Northward
C. Westward
D. Southward
Answer : A

23. On a ladder resting on a rough ground and leaning against a smooth vertical wall, the force of friction acts
A. Downwards at its upper end
B. Upwards at its upper end
C. Perpendicular to the wall at its upper end
D. Zero at its upper end
Answer : D

24. A smooth cylinder lying on its convex surface remains
A. In stable equilibrium
B. In unstable equilibrium
C. In neutral equilibrium
D. Out of equilibrium
Answer : B

25. Which of the following is a scalar quantity?
A. Energy
B. Momentum
C. Torque
D. Impulse
Answer : A

26. The resultant of two forces acting at right angles is 5 kgf and if they act at an angle of 60°, it is 37 kgf. The magnitudes of the forces are:
A. 2 kgf, 3 kgf
B. 3 kgf, 4 kgf
C. 4 kgf, 5 kgf
D. 5 kgf, 3 kgf
Answer : B

27. A rod 5 m in length is moving in a vertical plane. When it is inclined at 60° to horizontal, its lower end is moving horizontally at 3 m/sec and upper end is moving in vertical direction. The velocity of its upper end, is
A. 0.5 m/sec
B. 1.0 m/sec
C. 1.5 m/sec
D. 2.5 m/sec
Answer : B

28. A ball of mass 1 kg moving with a velocity of 2 m/sec collides a stationary ball of mass 2 kg and comes to rest after impact. The velocity of the second ball after impact will be
A. Zero
B. 0.5 m/sec
C. 1.0 m/sec
D. 2.0 m/sec
Answer : C

29. The following statement is one of the laws of Dynamic friction
A. The force of friction always acts in a direction opposite to that in which a body is moving
B. The magnitude of the kinetic friction bears a constant ratio to the normal reaction between two surfaces. The ratio being slightly less than that in the case of limiting friction
C. For moderate speeds the force of friction remains constant but decreases slightly with the increase of speed
D. All the above
Answer : D

30. A circular disc rotates at n rpm. The angular velocity of a circular ring of same mass and radius as the disc and to have the same angular momentum is
A. n rpm
B. n/2 rpm
C. n/4 rpm
D. 2n rpm
Answer : B

31. If a body moves in such a way that its velocity increases by equal amount in equal intervals of time, it is said to be moving with
A. A uniform retardation
B. A uniform acceleration
C. A variable acceleration
D. A variable retardation
Answer : C

32. When a body of mass M₁ is hanging freely and another of mass M₂ lying on a smooth inclined plane(?) are connected by a light index tensile string passing over a smooth pulley, the acceleration of the body of mass M₁, will be given by
A. g(M₁ + M₂ sin ?)/(M₁ + M₂) m/sec
B. g(M₁ - M₂ sin ?)/(M₁ + M₂) m/sec²
C. g(M₂ + M₁ sin ?)/(M₁ + M₂) m/sec²
D. g(M₂ × M₁ sin ?)/(M₂ - M₁) m/sec²
Answer : B

33. If the horizontal range is 2.5 times the greatest height, the angle of projection of the projectile, is
A. 57°
B. 58°
C. 59°
D. 60°
Answer : B

34. The moment of inertia of a hollow circular section whose external diameter is 8 cm and internal diameter is 6 cm, about centroidal axis, is
A. 437.5 cm⁴
B. 337.5 cm⁴
C. 237.5 cm⁴
D. 137.5 cm⁴
Answer : D

35. For a particle moving with a simple harmonic motion, the frequency is
A. Directly proportional to periodic time
B. Inversely proportional to periodic time
C. Inversely proportional to its angular velocity
D. Directly proportional to its angular velocity
Answer : B

36. In a lifting machine with efficiency 60%, an effort of 200 N is required to raise a load of 6 kN. The velocity ratio of the machine is
A. 30
B. 50
C. 60
D. 80
Answer : B

37. A flywheel of moment of inertia 20 kgm is acted upon by a tangential force of 5 N at 2 m from its axis, for 3 seconds. The increase in angular velocity in radian per second is
A. 1/2
B. 3/2
C. 2
D. 3
Answer : B

38. The resolved part of the resultant of two forces inclined at an angle ? in a given direction is
A. Algebraic sum of the resolved parts of the forces in the direction
B. Arithmetical sum of the resolved parts of the forces in the direction
C. Difference of the forces multiplied by cosine ?°
D. Sum of the forces multiplied by the tangent ?°
Answer : A

40. A particle of mass 2 kg executes simple harmonic motion of frequency 6/71 Hz and amplitude 0.25 m. Its maximum kinetic energy is
A. 4.5 J
B. 9.0 J
C. 12.0 J
D. 18.0 J
Answer : B

41. Total no of instantaneous centres of a machine having n links, is
A. n/2
B. n
C. (n - 1)
D. n (n - 1)/2
Answer : D

42. A 2 m long ladder rests against a wall and makes an angle of 30° with the horizontal floor. Where will be the instantaneous center of rotation when the ladder starts slipping? (i) 1.0 in from the wall (ii) 1.732 m from the wall (iii) 1.0 m above the floor (iv) 1.732 m above the floor The correct answer is
A. (i) and (iii)
B. (i) and (iv)
C. (ii) and (iii)
D. (ii) and (iv)
Answer : D

43. The ratio of the ranges on the inclined plane with motion upward and with motion downward for a given velocity, angle of projection will be
A. sin (? + ?)/sin (? - ?)
B. sin (? - ?)/sin (? + ?)
C. cos (? - ?)/cos (? + ?)
D. tan (? - ?)/tan (? + ?)
Answer : B

44. Which one of the following laws is not applicable to a simple pendulum?
A. The time period does not depend on its magnitude
B. The time period is proportional to its length l
C. The time period is proportional to l, where l is length
D. The time period is inversely proportional to g, where g is the acceleration due to gravity
Answer : B

45. A rigid body suspended vertically at a point and oscillating with a small amplitude under the action of the force of gravity, is called
A. Simple pendulum
B. Compound pendulum
C. Second's pendulum
D. None of these
Answer : B

46. Pick up the correct statement from the following. A rubber ball when strikes a wall rebounds but a lead ball of same mass and velocity when strikes the same wall, falls down
A. Rubber and lead balls undergo equal changes in momentum
B. Change in momentum suffered by lead ball is less that of rubber ball
C. Momentum of rubber ball is less than that of lead ball
D. None of these
Answer : D

47. A particle is executing simple harmonic motion in a line 1.0 m long. If the time of one complete vibration is 1 sec, then the maximum velocity of the particle is
A. 1.00 m/sec
B. 1.57 m/sec
C. 3.14 m/sec
D. 6.28 m/sec
Answer : C

48. Time period and length of a seconds pendulum respectively are
A. 1 sec and 99.4 cm
B. 1 sec and 92.7 cm
C. 2 sec and 99.4 cm
D. 2 sec and 92.7 cm
Answer : C

49. A rigid body is in a stable equilibrium if the application of any force
A. Can raise the CG of the body but cannot lower it
B. Tends to lower the CG of the body
C. Neither raises nor lowers the CG of the body
D. None of above
Answer : A

50. The torque produced by a force depends on (i) The magnitude of the force (ii) The direction of the force (iii) The point of application of the force relative to origin The correct answer is
A. Only (i)
B. Both (i) and (ii)
C. Both (i) and (iii)
D. All (i), (ii) and (iii)
Answer : D