Engineering Questions with Answers - Multiple Choice Questions

# Strength of Materials (MCQs) focuses on “Strain”

1 - Question

The property by which a body returns to its original shape after removal of the force is called __________
a) Plasticity
b) Elasticity
c) Ductility
d) Malleability
Explanation: When an external force acts on a body, the body tends to undergo some deformation. If the external force is removed and the body comes back to its original shape and size, the body is known as elastic body and this property is called elasticity.

2 - Question

The property of a material by which it can be beaten or rolled into thin plates is called __________
a) Malleability
b) Plasticity
c) Ductility
d) Elasticity
Explanation: A material can be beaten into thin plates by its property of malleability.

3 - Question

Which law is also called as the elasticity law?
a) Bernoulli’s law
b) Stress law
c) Hooke’s law
d) Poisson’s law
Explanation: The hooke”s law is valid under the elastic limit of a body. It itself states that stress is proportional to the strain within the elastic limit.

4 - Question

The materials which have the same elastic properties in all directions are called __________
a) Isotropic
b) Brittle
c) Homogeneous
d) Hard
Explanation: Same elastic properties in all direction is called the homogenity of a material.

5 - Question

A member which does not regain its original shape after removal of the load producing deformation is said __________
a) Plastic
b) Elastic
c) Rigid
d) None of the mentioned
Explanation: A plastic material does not regain its original shape after removal of load. An elastic material regain its original shape after removal of load.

6 - Question

The body will regain it is previous shape and size only when the deformation caused by the external forces, is within a certain limit. What is that limit?
a) Plastic limit
b) Elastic limit
c) Deformation limit
d) None of the mentioned
Explanation: The body only regain its previous shape and size only upto its elastic limit.

7 - Question

The materials which have the same elastic properties in all directions are called __________
a) Isotropic
b) Brittle
c) Homogenous
d) Hard
Explanation: Isotropic materials have the same elastic properties in all directions.

8 - Question

As the elastic limit reaches, tensile strain __________
a) Increases more rapidly
b) Decreases more rapidly
c) Increases in proportion to the stress
d) Decreases in proportion to the stress
Explanation: On reaching the tensile stress to the elastic limit after the proportionality limit, the stress is no longer proportional to the strain. Then the value of strain rapidly increases.

9 - Question

What kind of elastic materials are derived from a strain energy density function?
a) Cauchy elastic materials
b) Hypo elastic materials
c) Hyper elastic materials
d) None of the mentioned
Explanation: The hyper elastic materials are derived from a strain energy density function. A model is hyper elastic if and only if it is possible to express the cauchy stress tensor as a function of the deformation gradient.

10 - Question

What the number that measures an object’s resistance to being deformed elastically when stress is applied to it?
a) Elastic modulus
b) Plastic modulus
c) Poisson’s ratio
d) Stress modulus
Explanation: The elastic modulus is the ratio of stress to strain.

11 - Question

The law which states that within elastic limits strain produced is proportional to the stress producing it is known as _____________
a) Bernoulli’s law
b) Hooke’s law
c) Stress law
d) Poisson’s law
Explanation: Hooke’s law states that strain is directly proportional to strain produced by the stress when a material is loaded within the elastic limit.

12 - Question

For an isotropic, homogeneous and elastic material obeying Hooke’s law, the number of independent elastic constants is ____________
a) 2
b) 3
c) 9
d) 1
Explanation: There are 3 constants Young’s modulus, Shear modulus and Bulk modulus.

13 - Question

What is the factor of safety?
a) The ratio of stress to strain
b) The raio of permissible stress to the ultimate stress
c) The ratio of ultimate stress to the permissible stress
d) The ratio of longitudinal strain to stress
Explanation: Factor of safety is the ratio of ultimate stress to the permissible stress.

14 - Question

What is Hooke’s law for the 1-D system?
a) The relation between normal stress and the corresponding strain
b) The relation between shear stress and the corresponding strain
c) The relation between lateral strain and the corresponding stress
d) None of the mentioned
Explanation: For the 1-D system, the stress will be only in one direction. Lateral stress is for an area while normal stress is of a length.

15 - Question

Limit of proportionality depends upon ____________
a) Area of cross-section
c) Type of material
d) All of the mentioned
Explanation: The proportionality limit is proportional to the area of cross-section. The material type and loading type will have no influence on the proportionality limit.

16 - Question

The stress at which extension of a material takes place more quickly as compared to the increase in load is called ____________
a) Elastic point
b) Plastic point
c) Breaking point
d) Yielding point
Explanation: On the stress strain curve, on the elastic point the stress of a material takes place more quickly.

17 - Question

Which of these is a non-hoookean material?
a) Steel
b) Rubber
c) Aluminium
d) Copper
Explanation: Rubber is generally regarded as a “non-hookean” material because its elasticity is stress dependent and sensitive to temperature and loading rate.

18 - Question

Where in the stress-strain curve, the hooke’s law is valid?
a) Strain hardening region
b) Necking region
c) Elastic range
d) Valid everywhere
Explanation: The hooke’s law itself states that it is valid only up to the elastic range of the material I.e. only to that limit where the material is behaving elastic.

19 - Question

Highest value of stress for which Hooke’s law is applicable for a given material is called ____________
a) Stress limit
b) Strain limit
c) Proportional limit
d) Significant limit
Explanation: The hooke’s law is valid only when the stress is proportional to the strain, that is only in the proportionality limit.

20 - Question

The slope of the stress-strain curve in the elastic deformation region is ____________
a) Elastic modulus
b) Plastic modulus
c) Poisson’s ratio
d) None of the mentioned
Explanation: The elastic modulus is the ratio of stress and strain. So on the stress strain curve, it is the slope.

21 - Question

What is the stress-strain curve?
a) It is the percentage of stress and stain
b) It is the relationship between stress and strain
c) It is the difference between stress and strain
d) None of the mentioned
Explanation: The relationship between stress and strain on a graph is the stress strain curve. It represents the change in stress with change in strain.

22 - Question

Which point on the stress strain curve occurs after the proportionality limit?
a) Upper yield point
b) Lower yield point
c) Elastic limit
d) Ultimate point
Explanation: The curve will be stress strain proportional upto the proportionality limit. After these, the elastic limit will occur.

23 - Question

Which point on the stress strain curve occurs after the lower yield point?
a) Yield plateau
b) Upper yield point
c) Ultimate point
d) None of the mentioned
Explanation: The points on the curve comes in the given order, A. proportionality limit B. elastic limit C. upper yield point D. lower yield point E. yield plateau F. ultimate point G. breaking point.

24 - Question

Which point on the stress strain curve occurs after yield plateau?
a) lower yield point
b) Upper yield point
c) Ultimate point
d) Breaking point
Explanation: After the yield plateau the curve will go up to its maximum limit of stress which is its ultimate point.

25 - Question

Which point on the stress strain curve occurs after the ultimate point?
a) Last point
b) Breaking point
c) Elastic limit
d) Material limit
Explanation: After the ultimate point the value of stress will reduce on increasing of strain and ultimately the material will break.

26 - Question

Elastic limit is the point ____________
a) up to which stress is proportional to strain
c) Up to which if the load is removed, original volume and shapes are regained
d) None of the mentioned
Explanation: The elastic limit is that limit up to which any material behaves like an elastic material.

27 - Question

What is the point P shown on the stress strain curve?<br/> a) Upper yield point<br/>
b) Yield plateau<br/>
c) Elastic limit<br/>
d) Ultimate point

Explanation: It is the point showing the maximum stress to which the material can be subjected in a simple tensile stress.

28 - Question

What is the point P shown in the stress-strain curve?<br/> a) Lower yield point<br/>
b) Elastic limit<br/>
c) Proportionality limit<br/>
d) Breaking point

Explanation: The breaking point is the point where the material breaks. The breaking point will be the last point on the stress strain curve.

29 - Question

What is the point shown in the stress strain curve?<br/> a) Elastic limit<br/>
b) Lower yield point<br/>
c) Yield plateau<br/>
d) Lower strain point

Explanation: It is the lower yield point at which the curve levels off and plastic deformation begins.

30 - Question

Where is the necking region?
a) The area between lower yield point and upper yield point
b) The area between the plastic limit and elastic limit
c) The area between the ultimate point and initial point
d) The area between the ultimate point and rupture