Free Practice Quiz Question List

03 Mechanical Behavior: Stress, Strain, and Deformation Online Quiz Questions

Use this free practice quiz with 20 questions to review 03 Mechanical Behavior: Stress, Strain, and Deformation, test your knowledge, and prepare for your next test or exam.

20 questions

True or false

1 point

True or false: Engineering strain is calculated by dividing the change in gauge length by the original gauge length.

A
True
B
False

Choose one

1 point

Two materials are in their linear-elastic regions and are subjected to the same stress. Which conclusion follows if material A has a larger Young’s modulus than material B?

A
It means the material can always withstand a greater stress before yielding.
B
It means the material has less elastic strain under the same stress.
C
It means the material must be more ductile.
D
It means the material has a higher ultimate tensile strength.

True or false

1 point

True or false: In a typical ductile specimen, localized necking generally begins around the maximum engineering stress on the tensile curve.

A
True
B
False

Choose one

1 point

Which statement correctly distinguishes ductile behavior from brittle behavior?

A
A ductile material fractures with little plastic deformation, while a brittle material undergoes substantial plastic strain.
B
Ductility is determined only by the initial slope of the stress–strain curve.
C
A ductile material can undergo substantial plastic strain before fracture, while a brittle material fractures with little plastic deformation.
D
A brittle material must have a lower Young’s modulus than a ductile material.

Fill in the blank

1 point

The slope of the is the .

Written response

1 point

A tensile specimen with an original cross-sectional area of $30\,\text{mm}^2$ carries a force of $9\,\text{kN}$ . What is its engineering stress, calculated using the original area?

Written response

1 point

A gauge length of $120\,\text{mm}$ extends by $0.36\,\text{mm}$ . What is the engineering strain as a dimensionless decimal?

Choose one

1 point

A metal specimen has yielded and is then unloaded. What is the typical result?

A
It returns fully to its original dimensions because all deformation is elastic.
B
It recovers some elastic strain but retains a permanent change in dimensions.
C
It continues to deform until fracture, regardless of whether the load is removed.
D
It returns to its original dimensions only if the stress had been above the ultimate tensile strength.

Fill in the blank

1 point

When a clear yield point is absent, the 0.2% offset method starts its line at a strain of and draws the line to the initial elastic slope.

Choose all

1 point

Which statements about a typical engineering stress–strain curve for a ductile metal are correct? Select all that apply.

A
The slope of the initial linear-elastic region gives Young’s modulus.
B
The maximum engineering stress is the ultimate tensile strength.
C
The engineering stress must increase continuously until fracture.
D
The area under the curve up to fracture is related to toughness.

Choose one

1 point

A material has Young’s modulus $150\,\text{GPa}$ . Assuming it is in the linear-elastic region, what stress corresponds to a strain of $0.001$ ?

A
$15\,\text{MPa}$
B
$75\,\text{MPa}$
C
$150\,\text{MPa}$
D
$150\,\text{GPa}$

Choose all

1 point

Which statements about factors affecting stress–strain behavior and stress–strain measures are supported? Select all that apply.

A
Temperature can affect measured stress–strain behavior.
B
Engineering stress uses the changing cross-sectional area during deformation.
C
Loading rate can affect measured stress–strain behavior.
D
True stress and strain account for changing dimensions during deformation.

Open ended

1 point

Explain what the area under a tensile stress–strain curve represents up to a chosen strain, and how the area up to fracture relates to a material property.

Choose one

1 point

A ductile specimen necks after reaching its ultimate tensile strength. Which explanation best accounts for a later decrease in engineering stress even as the local section continues to deform?

A
Engineering stress uses the original area, so a falling force after necking can make the calculated value fall even as the local section continues to deform.
B
Engineering stress uses the changing local area, so the calculated value must fall whenever necking begins.
C
Necking means the specimen has already fractured, so no stress can be calculated afterward.
D
Engineering stress falls after the UTS because the original area becomes larger during deformation.

True or false

1 point

Under the usual sign convention for engineering strain, is tensile strain positive and compressive strain negative?

A
True
B
False

Choose one

1 point

A specimen with an original cross-sectional area of $60\,\text{mm}^2$ carries a tensile force of $12\,\text{kN}$ . What is its engineering stress?

A
20 MPa
B
120 MPa
C
200 MPa
D
720 MPa

Written response

1 point

What term names the strain remaining after a yielded specimen is unloaded?

Written response

1 point

A gauge length of $150\,\text{mm}$ extends by $0.30\,\text{mm}$ . What is the engineering strain as a decimal?

Choose one

1 point

Two materials are in the linear-elastic region and experience the same stress. Material X has a larger Young’s modulus than Material Y. Which conclusion follows from this information?

A
It necessarily has a greater yield strength.
B
It has less elastic strain for the same applied stress in the linear-elastic region.
C
It must undergo more plastic deformation before fracture.
D
It must have a higher ultimate tensile strength.

Choose one

1 point

On an engineering tensile stress–strain curve, what does the area under the curve from the start up to a specified strain represent?

A
The work done per unit original volume up to that strain.
B
The specimen’s original cross-sectional area.
C
The maximum engineering stress reached at any point.
D
The permanent strain remaining after unloading.