Engineering Mechanics: Master the Fundamentals of Statics, Dynamics, and Materials Science

Question 1

Which of the following is not a fundamental principle of mechanics that is included in this unit?

Accepted Answer

Thermodynamics

Answer

Statics

Answer

Dynamics

Answer

Materials science

Question 2

A force of 10 N acts on an object with a mass of 2 kg. What is the acceleration of the object?

Accepted Answer

2 m/s²

Answer

0.5 m/s²

Answer

5 m/s²

Answer

10 m/s²

Question 3

Which of the following is the correct unit for moment of inertia?

Accepted Answer

kg m²

Answer

kg

Answer

kg m

Answer

kg m³

Question 4

Which of the following materials has the highest yield strength?

Accepted Answer

Steel

Answer

Concrete

Answer

Wood

Answer

Rubber

Question 5

Which of the following is not a type of truss covered in this unit?

Accepted Answer

Moment frame

Answer

Pratt truss

Answer

Warren truss

Answer

Vierendeel truss

Question 6

Which of the following is NOT a fundamental principle of mechanics?

Accepted Answer

Fluid mechanics

Answer

Statics

Answer

Dynamics

Answer

Materials science

Question 7

The equilibrium of a rigid body subjected to external forces is determined by the:

Accepted Answer

Equations of equilibrium

Answer

Equations of motion

Answer

Conservation laws

Answer

Stress-strain relationships

Question 8

According to Newton's second law of motion, the acceleration of an object is:

Accepted Answer

Proportional to the mass of the object

Answer

Inversely proportional to the force acting on it

Answer

Proportional to the square of the force acting on it

Answer

Proportional to the velocity of the object

Question 9

Which of the following is characteristic of a brittle material?

Accepted Answer

Low elongation at failure

Answer

High yield strength

Answer

Ductile behavior

Answer

High energy absorption capacity

Question 10

For a cantilever beam subjected to a point load at its free end, the bending moment diagram exhibits a:

Accepted Answer

Linear variation

Answer

Parabolic variation

Answer

Triangular variation

Answer

Curvilinear variation

Question 11

The natural frequency of a damped spring-mass system is:

Accepted Answer

Less than the natural frequency of the undamped system

Answer

Greater than the natural frequency of the undamped system

Answer

Equal to the natural frequency of the undamped system

Answer

Unrelated to the natural frequency of the undamped system

Question 12

Which of the following materials is an electrical insulator?

Accepted Answer

Rubber

Answer

Copper

Answer

Aluminum

Answer

Steel

Question 13

The efficiency of a Carnot heat engine operating between two reservoirs is:

Accepted Answer

Equal to the ratio of the absolute temperatures of the two reservoirs

Answer

Greater than the ratio of the absolute temperatures of the two reservoirs

Answer

Less than the ratio of the absolute temperatures of the two reservoirs

Answer

Unrelated to the ratio of the absolute temperatures of the two reservoirs

Question 14

Which of the following is **not** a fundamental force in mechanics?

Accepted Answer

Frictional force

Answer

Gravitational force

Answer

Electromagnetic force

Answer

Nuclear force

Question 15

A rigid body is considered to be in equilibrium when:

Accepted Answer

Both net force and net torque acting on it are zero

Answer

Net force acting on it is zero

Answer

Net torque acting on it is zero

Answer

Neither net force nor net torque acting on it is zero

Question 16

The SI unit of force is the:

Accepted Answer

Newton

Answer

Kilogram

Answer

Meter

Answer

Second

Question 17

For an object moving with a constant velocity, which of the following statements is true?

Accepted Answer

Forces acting on the object are balanced

Answer

Forces acting on the object are unbalanced

Answer

Net force acting on the object is non-zero

Answer

Net torque acting on the object is non-zero

Question 18

Which of the following materials typically has the highest tensile strength?

Accepted Answer

Steel

Answer

Aluminum

Answer

Copper

Answer

Plastic

Question 19

The yield strength of a material can be defined as the:

Accepted Answer

Maximum stress it can withstand before permanent deformation occurs

Answer

Maximum stress it can withstand before breaking

Answer

Stress at which it starts to yield

Answer

Stress at which it reaches its elastic limit

Question 20

A force of 100 N acts on a body of mass 20 kg. What is the resulting acceleration? (F=ma)

Accepted Answer

2 m/s²

Answer

5 m/s²

Answer

10 m/s²

Answer

15 m/s²

Question 21

Which of the following is NOT a scalar quantity? (Scalar quantities have only magnitude, while vector quantities have both magnitude and direction)

Accepted Answer

Velocity

Answer

Mass

Answer

Temperature

Answer

Time

Question 22

Which type of stress is caused by a force applied perpendicular to the cross-sectional area of a material?

Accepted Answer

Tensile stress

Answer

Compressive stress

Answer

Shear stress

Answer

Torsional stress

Question 23

A beam of length L is simply supported at its ends and subjected to a uniformly distributed load. The maximum bending moment in the beam is given by which formula? (M=wL²/8)

Accepted Answer

wL²/8

Answer

wL²/12

Answer

wL²/16

Answer

wL²/32

Question 24

The efficiency of a machine is defined as the ratio of output work to input work. True or False?

Accepted Answer

True

Answer

False

Question 25

The modulus of elasticity of a material is a measure of its stiffness. True or False?

Accepted Answer

True

Answer

False

Question 26

Which of the following is a scalar quantity that describes the hotness or coldness of a substance?

Accepted Answer

Temperature

Answer

Displacement

Answer

Velocity

Answer

Mass

Question 27

Which unit is used to measure the moment of inertia of an object?

Accepted Answer

kg·m²

Answer

kg·s²

Answer

N·m

Answer

J

Question 28

Which material is known for having the greatest tensile strength?

Accepted Answer

Steel

Answer

Aluminum

Answer

Concrete

Answer

Wood

Question 29

Which equation correctly defines work?

Accepted Answer

W = F·d

Answer

W = F·x

Answer

W = F·t

Answer

W = F·v

Question 30

A machine has an overall efficiency of 70%. If the input power is 1000 W, what is the output power?

Accepted Answer

700 W

Answer

300 W

Answer

500 W

Answer

900 W

Question 31

A force of 100N is acting on a 10 kg object. What is the object's acceleration according to Newton's second law of motion?

Accepted Answer

10 m/s²

Answer

100 m/s²

Answer

1 m/s²

Question 32

For a body to be in equilibrium under the action of multiple forces, which condition must be satisfied?

Accepted Answer

The vector sum of the forces acting on the body must be zero.

Answer

The forces must be equal in magnitude.

Answer

The forces must act in opposite directions.

Answer

The forces must act in the same direction.

Question 33

Which material is known for having the highest Young's modulus, indicating its stiffness?

Accepted Answer

Steel

Answer

Rubber

Answer

Plastic

Answer

Wood

Question 34

Which equation represents the conservation of energy principle?

Accepted Answer

E = K + U

Answer

P = IV

Answer

F = ma

Answer

W = Fd

Question 35

What is the primary purpose of a gearbox in a mechanical system?

Accepted Answer

To change the speed and torque of a rotating shaft

Answer

To reduce noise and vibration

Answer

To lubricate bearings

Answer

To transmit power between shafts

Question 36

A vertical column of length L is subjected to an axial compressive load P. What is the critical buckling load for this column, according to Euler's formula?

Accepted Answer

π²EI/L²

Answer

2π²EI/L²

Answer

EI/L²

Answer

4π²EI/L²

Question 37

A shaft is subjected to a torque T. What is the shear stress (τ) developed in the shaft at a radial distance 'r' from the center, given that the polar moment of inertia of the shaft's cross-section is 'J'?

Accepted Answer

Tr/J

Answer

T/r

Answer

2Tr/J

Answer

Tr²/J

Question 38

A material has a yield strength of 200 MPa. What is the maximum stress that can be applied to the material without causing permanent deformation?

Accepted Answer

200 MPa

Answer

400 MPa

Answer

300 MPa

Answer

100 MPa

Question 39

Trusses are structures composed of interconnected members forming triangular units. What is the primary advantage of using trusses in engineering structures?

Accepted Answer

Increased strength and stability due to the inherent rigidity of triangular shapes.

Answer

Improved aesthetics.

Answer

Ease of construction and assembly.

Answer

Reduced weight compared to solid beams.

Question 40

A 100 kg crate is lifted vertically upward with an acceleration of 2 m/s². Calculate the tension in the rope used to lift the crate. (Assume gravitational acceleration, g = 9.8 m/s²)

Accepted Answer

1180 N

Answer

1020 N

Answer

800 N

Answer

980 N

Question 41

A uniform beam of length 6 m is supported by two vertical ropes at its ends. A load of 1000 N is applied at the center of the beam. What is the tension in each rope?

Accepted Answer

500 N

Answer

1000 N

Answer

250 N

Answer

750 N

Question 42

A car of mass 1000 kg is traveling at a speed of 30 m/s. Calculate the kinetic energy of the car.

Accepted Answer

450 kJ

Answer

300 kJ

Answer

900 kJ

Answer

600 kJ

Question 43

A steel rod of length 1 m has a cross-sectional area of 1 cm². The rod elongates by 0.001 m when a force of 1000 N is applied. Determine the Young's modulus of the steel.

Accepted Answer

200 GPa

Answer

100 GPa

Answer

300 GPa

Question 44

A pulley with a radius of 10 cm is used to lift a load of 50 kg. If the effort required to lift the load is 25 kg, what is the mechanical advantage of the pulley?

Accepted Answer

2

Answer

1

Answer

3

Question 45

What is the moment of inertia of a solid cylinder about its central axis, given its mass 'm' and radius 'r'?

Accepted Answer

1/2 * m * r²

Answer

1/4 * m * r²

Answer

m * r

Question 46

Which of the following statements about friction is true?

Accepted Answer

Friction opposes motion between two surfaces in contact.

Answer

Friction is always a negative force.

Answer

Friction is independent of the surface area in contact.

Question 47

A projectile is launched vertically upward with a velocity of 20 m/s. What is the maximum height it will reach?

Accepted Answer

20.4 m

Answer

10.2 m

Answer

30.6 m

Question 48

Which of the following is a scalar quantity?

Accepted Answer

Temperature

Answer

Acceleration

Answer

Displacement

Answer

Velocity

Question 49

The work done by a force is:

Accepted Answer

Force × Distance × Cosine of the angle between the force and displacement

Answer

Force × Distance × Sine of the angle between the force and displacement

Answer

Force × Distance