Home

Engineering Mechanics MCQ Solved Paper for IBPS RRB

Thursday 9th of March 2023

Sharing is caring

Downlaod Engineering Mechanics MCQ PDF
1. A smooth cylinder lying on a __________ is in neutral equilibrium.
A. Curved surface
B. Convex surface
C. Horizontal surface
D. None of these
Answer : C
2. The rate of change of momentum is directly proportional to the impressed force, and takes place in the same direction in which the force acts. This statement is known as
A. Newton's first law of motion
B. Newton's second law of motion
C. Newton's third law of motion
D. None of these
Answer : B
3. Frictional force encountered after commencement of motion is called
A. Limiting friction
B. Kinematic friction
C. Frictional resistance
D. Dynamic friction
Answer : D
4. Which of the following do not have identical dimensions?
A. Momentum and impulse
B. Torque and energy
C. Torque and work
D. Moment of a force and angular momentum.
Answer : D
5. If the body falls freely under gravity, then the gravitational acceleration is taken as
A. +8.9 m/s2
B. -8.9 m/s2
C. +9.8 m/s2
D. -9.8 m/s2
Answer : C
6. If a number of forces are acting at a point, their resultant will be inclined at an angle ? with the horizontal, such that
A. tan? = ?H/?V
B. tan? = ?V/?H
C. tan? = ?V × ?H
D. tan? = ?(?V + ?H)
Answer : B
7. If the resultant of two equal forces has the same magnitude as either of the forces, then the angle between the two forces is
A. 30°
B. 60°
C. 90°
D. 120°
Answer : D
8. The velocity of a body on reaching the ground from a height h, is
A. 2.?(gh)
B. ?(gh)
C. ?(2gh)
D. 2g.?h
Answer : C
9. According to parallel axis theorem, the moment of inertia of a section about an axis parallel to the axis through centre of gravity (i.e. IP) is given by(where, A = Area of the section, IG = Moment of inertia of the section about an axis passing through its C.G., and h = Distance between C.G. and the parallel axis.)
A. IP = IG + Ah2
B. IP = IG - Ah2
C. IP = IG / Ah2
D. IP = Ah2 / IG
Answer : A
10. The moment of a force
A. Is the turning effect produced by a force, on the body, on which it acts
B. Is equal to the product of force acting on the body and the perpendicular distance of a point and the line of action of the force
C. Is equal to twice the area of the triangle, whose base is the line representing the force and whose vertex is the point, about which the moment is taken
D. All of the above
Answer : D
11. If a number of forces are acting at a point, their resultant is given by
A. (?V)2 + (?H)2
B. ?[(?V)2 + (?H)2]
C. (?V)2 +(?H)2 +2(?V)(?H)
D. ?[(?V)2 +(?H)2 +2(?V)(?H)]
Answer : B
12. A body will begin to move down an inclined plane if the angle of inclination of the plane is _________ the angle of friction.
A. Equal to
B. Less than
C. Greater than
D. None of these
Answer : C
13. A block of mass m1, placed on an inclined smooth plane is connected by a light string passing over a smooth pulley to mass m2, which moves vertically downwards as shown in the below figure. The tension in the string is
A. m1/m2
B. m1. g. sin ?
C. m1.m2/m1 + m2
D. m1. m2.g (1 + sin ?)/(m1 + m2)
Answer : D
14. Static friction is always __________ dynamic friction.
A. Equal to
B. Less than
C. Greater than
D. None of these
Answer : C
15. The M.I. of hollow circular section about a central axis perpendicular to section as compared to its M.I. about horizontal axis is
A. Same
B. Double
C. Half
D. Four times
Answer : B
16. The force applied on a body of mass 100 kg to produce an acceleration of 5 m/s2, is
A. 20 N
B. 100 N
C. 500 N
D. None of these
Answer : C
17. The total energy possessed by a system of moving bodies
A. Is constant at every instant
B. Varies from point to point
C. Is maximum in the start and minimum at the end
D. Is minimum in the start and maximum at the end
Answer : A
18. If three forces acting in one plane upon a rigid body, keep it in equilibrium, then they must either
A. Meet in a point
B. Be all parallel
C. At least two of them must meet
D. All the above are correct
Answer : D
19. The velocity ratio in case of an inclined plane inclined at angle ? to the horizontal and weight being pulled up the inclined plane by vertical effort is
A. sin?
B. cos?
C. tan?
D. cosec?
Answer : A
20. A body of weight W is required to move up on rough inclined plane whose angle of inclination with the horizontal is ?. The effort applied parallel to the plane is given by (where ? = tan? = Coefficient of friction between the plane and the body.)
A. P = W tan?
B. P = W tan (? + ?)
C. P = W (sin? + ?cos?)
D. P = W (cos? + ?sin?)
Answer : C
21. The range of projectile will be maximum for a given velocity of projectile, when the angle of projection (?) is
A. ?/2
B. 30° + ?/2
C. 45° + ?/2
D. 60° + ?/2
Answer : C
22. In a framed structure, as shown in the below figure, the forces in the members AB and BC are respectively
A. ?3. W (tensile) and 2W (compressive)
B. 2W (tensile) and ?3. W (compressive)
C. 2?3. W (tensile) and 2?3. W (compressive)
D. None of the above
Answer : A
23. In a screw jack, the effort required to lower the load is __________ the effort required to raise the same load.
A. Less than
B. Equal to
C. More than
D. None of these
Answer : A
24. Kinetic friction is the
A. Tangent of angle between normal reaction and the resultant of normal reaction and the limiting friction
B. Ratio of limiting friction and normal reaction
C. The friction force acting when the body is just about to move
D. The friction force acting when the body is in motion
Answer : D
25. Centre of gravity of a thin hollow cone lies on the axis at a height of
A. One-fourth of the total height above base
B. One-third of the total height above base
C. One-half of the total height above base
D. Three-eighth of the total height above the base
Answer : B
26. If three forces acting in different planes can be represented by a triangle, these will be in
A. Non-equilibrium
B. Partial equilibrium
C. Full equilibrium
D. Unpredictable
Answer : A
27. The law of motion involved in the recoil of gun is
A. Newton's first law of motion
B. Newton's second law of motion
C. Newton's third law of motion
D. None of these
Answer : C
28. The amplitude is always __________ radius of the circle.
A. Equal to
B. Less than
C. Greater than
D. None of these
Answer : A
29. The rate of doing work is known as
A. Potential energy
B. Kinetic energy
C. Power
D. None of these
Answer : C
30. The maximum efficiency of a screw jack is
A. (1 - sin?)/(1 + sin?)
B. (1 + sin?)/(1 - sin?)
C. (1 - tan?)/(1 + tan?)
D. (1 + tan?)/(1 - tan?)
Answer : A
31. The bellow figure shows the two equal forces at right angles acting at a point. The value of force R acting along their bisector and in opposite direction is
A. P/2
B. 2P
C. ?2 × P
D. P/?2
Answer : C
32. When a body of mass moment of inertia I (about a given axis) is rotated about that axis with an angular velocity to, then the kinetic energy of rotation is
A. I?
B. I?2
C. 0.5 I?
D. 0.5 I?2
Answer : D
33. The moment of inertia of a thin disc of mass m and radius r, about an axis through its centre of gravity and perpendicular to the plane of the disc is
A. mr2/2
B. mr2/4
C. mr2/6
D. mr2/8
Answer : A
34. The energy possessed by a body, for doing work by virtue of its position, is called
A. Potential energy
B. Kinetic energy
C. Electrical energy
D. Chemical energy
Answer : A
35. Pick up wrong statement about friction force for dry surfaces. Friction force is
A. Proportional to normal load between the surfaces
B. Dependent on the materials of contact surface
C. Proportional to velocity of sliding
D. Independent of the area of contact surfaces
Answer : C
36. One joule is equal to
A. 0.1 N-m
B. 1 N-m
C. 10 N-m
D. 100 N-m
Answer : B
37. The moment of inertia of a solid cone of mass m and base radius r about its vertical axis is
A. 3mr2/5
B. 3mr2/10
C. 2mr2/5
D. 4mr2/5
Answer : B
38. The unit of work or energy in S.I. units is
A. Newton
B. Pascal
C. Watt
D. Joule
Answer : D
39. When two elastic bodies collide with each other,
A. The two bodies will momentarily come to rest after collision
B. The two bodies tend to compress and deform at the surface of contact
C. The two bodies begin to regain their original shape
D. All of the above
Answer : D
40. Least force required to draw a body up the inclined plane is W sin (plane inclination + friction angle) applied in the direction
A. Along the plane
B. Horizontally
C. Vertically
D. At an angle equal to the angle of friction to the inclined plane
Answer : D
41. The forces, which meet at one point and their lines of action also lie on the same plane, are known as
A. Coplanar concurrent forces
B. Coplanar non-concurrent forces
C. Non-coplanar concurrent forces
D. Non-coplanar non-concurrent forces
Answer : A
42. A ladder is resting on a smooth ground and leaning against a rough vertical wall. The force of friction will act
A. Towards the wall at its upper end
B. Away from the wall at its upper end
C. Downward at its upper end
D. Upward at its upper end
Answer : D
43. During elastic impact, the relative velocity of the two bodies after impact is __________ the relative velocity of the two bodies before impact.
A. Equal to
B. Equal and opposite to
C. Less than
D. Greater than
Answer : B
44. The moment of inertia of a solid sphere of mass m and radius r is
A. 2mr2/3
B. 2mr2/5
C. mr2
D. mr2/2
Answer : B
45. The unit of moment of inertia of an area is
A. kg-m2
B. kg-m-s2
C. kg/m2
D. m4
Answer : D
46. The point, through which the whole weight of the body acts, irrespective of its position, is known as
A. Moment of inertia
B. Centre of gravity
C. Centre of percussion
D. Centre of mass
Answer : B
47. The linear velocity of a body rotating at ? rad/s along a circular path of radius r is given by
A. ?/r
B. ?.r
C. ?2/r
D. ?2.r
Answer : B
48. Three forces acting on a rigid body are represented in magnitude, direction and line of action by the three sides of a triangle taken in order. The forces are equivalent to a couple whose moment is equal to
A. Area of the triangle
B. Twice the area of the triangle
C. Half the area of the triangle
D. None of these
Answer : B
49. The centre of gravity a T-section 100 mm × 150 mm × 50 mm from its bottom is
A. 50 mm
B. 75 mm
C. 87.5 mm
D. 125 mm
Answer : C
50. Lami's theorem states that
A. Three forces acting at a point will be in equilibrium
B. Three forces acting at a point can be represented by a triangle, each side being proportional to force
C. If three forces acting upon a particle are represented in magnitude and direction by the sides of a triangle, taken in order, they will be in equilibrium
D. If three forces acting at a point are in equilibrium, each force is proportional to the sine of the angle between the other two
Answer : D
Downlaod Engineering Mechanics MCQ PDF

Sharing is caring

Related Post