Engineering Mechanics MCQ Quiz

6. A couple consists of......

5. The moment of a force about any point is geometrically equal to……….area of the triangle whose base is the line representing the force and vertex is the point about which the moment is taken.

4. If a number of forces are acting simultaneously on a particle, then the resultant of these forces will have the same effect as produced by the all the forces. This is known as,

3. For a non-concurrent force system to be in equilibrium

2. In order to determine the effects of a force acting on a body, we must know

1. Which of the following statement is correct?

61. A car negotiates a curve of radius 100 m at 25 m/sec. The angle to the horizontal at which the road must be banked to prevent sideways friction on the car wheels is tan"1 x, where x is (Assume g = 10 m/sec2 )

60. A stone was thrown vertically upwards from the ground with a velocity of 50 m/sec. After 5 seconds another stone was thrown vertically upwards from the same place. If both the stones strike the ground at the same time, then the velocity with which the second stone was thrown should be (Assume g = 10 m/sec2 )

59. The angular speed of a car taking a circular turn of radius 100 m at 36 km/hr will be

58. Two objects moving with uniform speeds are 5 m apart after 1 second when they move towards each other and are 1 m apart when they move in the same direction. The speeds of the objects are

57. A particle is dropped from a height of 3 m on a horizontal floor, which has a coefficient of restitution with the ball of 1/2. The height to which the ball will rebound after striking the floor is

56. A ball moving on a smooth horizontal table hits a rough vertical wall, the coefficient of restitution between ball and wall being 1/3. The ball rebounds at the same angle. The fraction of its kinetic energy lost is

55. If a lead ball with a certain velocity is made to strike a wall, it does not rebound. But if a rubber ball of same mass and velocity strikes the same wall, it rebounds. Select correct reason from the following

54. The loss of kinetic energy due to direct impact of two bodies depends on

53. The total momentum of two bodies remains constant after collision or any other mutual action. This is known as

52. Which of the following statement is wrong?

51. The shape of a suspended cable for a uniformly distributed load over it is

50.  Free body diagram is an

49.  In a lifting machine a weight of 5 kN is lifted through 200 mm by an effort of 0.1 kN moving through 15 m. The mechanical advantage and velocity ratio of the machine are respectively

48.  The condition for a lifting machine to be reversible is that its efficiency should be

47. If a body is lying on a plane whose inclination with the horizontal is less than the angle of friction, then

46.  A heavy ladder resting on floor and against a vertical wall may not be in equilibrium if

45. One Newton is equivalent to

44.  In SI units, the units of force and energy are respectively

43.  The unit of rotational inertia of a body in C.G.S system is

42.  Two masses of 10 kg and 15 kg are connected to two ends of an inextensible rope and passing over a smooth pulley. The 10 kg mass is lying over a rough plane, which is inclined at an angle of 25º with the horizontal. If this angle is made 30º, then

41. Which of the following statement is wrong?

40. The frequency of vibration in case of simple harmonic motion

39.  The periodic time of a body moving with simple harmonic motion

38.  One end of an elastic string of natural length / and modulus X is kept fixed while to the other end is attached a particle of mass m which is hanging freely under gravity. The particle is pulled down vertically through a distance x, held at rest and then released. The motion is

37.  The member forces in a statically indeterminate truss

36.  Free body diagram is an

35.  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

34. A stone is thrown up a slope of inclination 60° to the horizontal. At what angle to the slope must the stone be thrown so as to land as far as possible from the point of projection?

33.  A funicular polygon cannot be made to pass through

32.  If the direction of projection bisects the angle between the vertical and the inclined plane, then the range of projectile on the inclined plane is

31.  The maximum value of the horizontal range for a projectile projected with a velocity of 98 m/sec is

30. For a given velocity of a projectile, the range is maximum when the angle of projection is

29.  A flywheel of moment of inertia 20 kg-m2 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

28.  A particle moves in a straight line and its position is defined by the equation x = 6 t2 - t 3 where t is expressed in seconds and x in metres. The maximum velocity during the motion is

27. If the angular distance, 0 = 2t3 - 3t2, the angular acceleration at t = 1 sec. is

26.  Rate of change of angular momentum is equal to

25. The time of flight of a projectile on un upward inclined plane depends upon

24. The graphical method of determining the forces in the members of a truss is based on

23.  The ratio of the speed of a rolling cylinder to the speed of sliding cylinder is

22. The torque produced by a force depends on

21.  The angular speed of a car while taking a circular turn of radius 100 m at 36 km/hour, is

20.  Two circular discs of same weight and thickness are made from metals having different densities. Which disc will have the larger rotational inertia about its central axis?

19.  Which of the following represents the state of neutral equilibrium?

18.  The angles between two forces to make their resultant a minimum and a maximum respectively are

17.  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

16.  The force polygon representing a set of forces in equilibrium is a

15. If the resultant of two forces has the same magnitude as either of the force, then the angle between the two forces is

14. A force P of 50 N and another force Q of unknown magnitude act at 90° to each other. They are balanced by a force of 130 N. The magnitude of Q is

13. The moment of inertia of a triangular section of base (b) and height (h) about an axis through its c. g. and parallel to the base is given by the relation,

12. The moment of inertia of a triangular section of base (b) and height (h) about an axis passing through its vertex and parallel to the base is ............ as that passing through its C.G. and parallel to the base.

11.  If the sum of all the forces acting on a body is zero, then the body may be in equilibrium provided the forces are

10.  If a body is in equilibrium. We may conclude that

9.  The Lami’s Theorem is applicable only for

8. According to Lami’s Theorem, the three forces

7. A system of forces acting on a lamina is shown in the given figure. The resultant of the force system will meet AB at