# Engineering Mechanics Multiple Choice Questions(MCQs)& Answers

# CONCEPTS & THEORIES

engineering-mechanicsEngineering mechanics is the application of mechanics to solve problems involving common engineering elements. The goal of Engineering Mechanics course is to expose students to problems in mechanics as applied to plausibly real-world scenarios. Problems of particular types are explored in detail in the hopes that students will gain an inductive understanding of the underlying principles at work.

## Types of Engineering Mechanics:

Engineering mechanics can be classified into two types-

**A. Statics:**Statics is the branch of mechanics that deals with the study of objects at rest. Objects at rest may or may not be under the influence of forces.

**B. Dynamics:**Dynamics is the branch of mechanics that deals with the study of objects in motion and the forces causing such motion.

Dynamics can be further classified into two types-

**1. Kinematics:**Kinematics is the study of the motion of bodies without consideration of the cause of the motion. Kinematics deals with the space-time relationship of the motion of a body. Some examples of kinematic concepts are displacement, velocity and acceleration.

**2. Kinetics:**Kinetics is the branch of mechanics which deals with the study of the motion of bodies by considering the cause of motion.

## Some basic terms used in Mechanics

**Mass:**The quantity of the matter possessed by a body is called mass. The mass of a body can not change unless the body is damaged and part of it is physically separated.

**Length:**It is a concept to measure linear distances.

**Time:**Time is the measure of succession of events. The successive event selected is the rotation of earth about its own axis and this is called a day.

**Space:**Any geometric region in which the study of a body has been done is called space.

**Displacement:**It is defined as the distance moved by a body/particle in the specified direction.

**Velocity:**The rate of change of displacement with respect to time is defined as velocity.

**Acceleration:**It is the rate of change of velocity with respect to time.

**Momentum:**The product of mass and velocity is called momentum. Thus

**Momentum = Mass × Velocity**

**Particle:**It can be defined as an object which has only mass and no size.

# QUESTIONS

# Engineering Multiple Choice Questions(MCQs)& Answers

1
three forces acting in one plane upon a rigid body, keep it in equilibrium, then they must either

Answer: all the above are correct

2
A single force and a couple acting in the same plane upon a rigid body

Answer: cannot balance each other

3
The maximum frictional force which comes into play when a body just begins to slide over another surface is called

Answer: limiting friction

5
The effort required to lift a load W on a screw jack with helix angle a and angle of friction <j) is equal to

Answer: Wtan(a + )

10
Limiting force of friction is the

Answer: the friction force acting when the body is just about to move

11
If rain is falling in the opposite direction of the movement of a pedestrain, he has to hold his umbrella

Answer: less inclined when standing

12
A particle moves along a straight line such that distance (x) traversed in t seconds is given by x = t2 (t – 4), the acceleration of the particle will be given by the equation

Answer: 6f-8

13
Pick up wrong statement about friction force for dry surfaces. Friction force is

Answer: proportional to velocity of sliding

16
On the ladder resting on the ground and leaning against a smooth vertical wall, the force of friction will be

Answer: Gross vehicle mass

17
On a ladder resting on smooth ground and leaning against vertical wall, the force of friction will be

Answer: upwards at its upper end

18
Which one of the following statements is not correct

Answer: the sine of the angle of repose is equal to coefficient to friction

20
Least force required to draw a body up the inclined plane is W sin (plane inclination + friction angle) applied in the direction

Answer: at an angle equal to the angle of friction to the inclined plane

21
According to principle of transmissibility of forces, the effect of a force upon a body is

Answer: the same at every point in its line of action

24
The forces, which meet at one point, but their lines of action do not lie in a plane, are called

Answer: non-coplanar concurrent forces

25
The weight of a body is due to

Answer: gravitational force of attraction towards the center of the earth

29
Which of the following do not have identical dimensions ?

Answer: Moment of a force and angular momentum.

30
The resolved part of the resultant of two forces inclined at an angle 9 in a given direction is equal to

Answer: the algebraic sum of the resolved parts of the forces in the given direction

31
The algebraic sum of the resolved parts of a number of forces in a given direction is equal to the resolved part of their resultant in the same direction. This is as per the principle of

Answer: resolution of forces

32
If two equal forces of magnitude P act at an angle 9°, their resultant will be

Answer: IP cos 9/2

34
If a number of forces act simultaneously on a particle, it is possible

Answer: to replace them by a single force

41
three forces acting in one plane upon a rigid body, keep it in equilibrium, then they must either

Answer: all the above are correct

42
A single force and a couple acting in the same plane upon a rigid body

Answer: cannot balance each other

43
The maximum frictional force which comes into play when a body just begins to slide over another surface is called

Answer: limiting friction

45
The effort required to lift a load W on a screw jack with helix angle a and angle of friction <j) is equal to

Answer: Wtan(a + )

50
Limiting force of friction is the

Answer: the friction force acting when the body is just about to move

51
If rain is falling in the opposite direction of the movement of a pedestrain, he has to hold his umbrella

Answer: less inclined when standing

52
A particle moves along a straight line such that distance (x) traversed in t seconds is given by x = t2 (t – 4), the acceleration of the particle will be given by the equation

Answer: 6f-8

53
Pick up wrong statement about friction force for dry surfaces. Friction force is

Answer: proportional to velocity of sliding

56
On the ladder resting on the ground and leaning against a smooth vertical wall, the force of friction will be

Answer: Gross vehicle mass

57
On a ladder resting on smooth ground and leaning against vertical wall, the force of friction will be

Answer: upwards at its upper end

58
Which one of the following statements is not correct

Answer: the sine of the angle of repose is equal to coefficient to friction