MF - Chapter 05: Stress and Strain Concepts

What are the types of stress?

• Acute stress, Episodic acute stress, Chronic stress, Traumatic stress

• Physical stress, Emotional stress, Mental stress

Define elastic modulus.

• A measure of a material's color

• A measure of a material's volume

• A measure of a material's stiffness

• A measure of a material's weight

State Hooke's Law.

• F = ax

• F = -kx

• F = mx

• F = kx

What is the yield point in stress-strain curve?

• The yield point is the stress value at which plastic deformation begins.

• The yield point is the stress value at which the material breaks.

• The yield point is the stress value at which the material reaches maximum strength.

• The yield point is the stress value at which the material becomes elastic.

Explain ultimate tensile strength.

• Ultimate tensile strength is the ability of a material to stretch without breaking.

• Ultimate tensile strength is the minimum amount of tensile stress a material can withstand before breaking.

• Ultimate tensile strength is the maximum amount of tensile stress a material can withstand before breaking or fracturing.

• Ultimate tensile strength is the maximum amount of compressive stress a material can withstand before breaking.

Discuss the factors affecting strain.

• Length, time, and speed

• Density, volume, and temperature

• Material type, color, and smell

• Modulus of elasticity, cross-sectional area, and applied force.

How is compressive stress different from tensile stress?

• Compressive stress elongates the object, while tensile stress shortens it.

• Compressive stress has no effect on the object, while tensile stress shortens it.

• Compressive stress elongates the object, while tensile stress has no effect on it.

• Compressive stress shortens the object, while tensile stress elongates it.

Calculate the elastic modulus if stress is 500 MPa and strain is 0.02.

• 10000 MPa

• 30000 MPa

• 25000 MPa

• 15000 MPa

What happens to a material beyond its yield point?

• It becomes more flexible

• It returns to its original shape

• It becomes stronger

• Permanent deformation or plastic deformation occurs

Why is Hooke's Law only applicable within the elastic limit?

• Hooke's Law is only applicable within the elastic limit because it is a recent discovery

• Hooke's Law is only applicable within the elastic limit because beyond this limit, the material undergoes permanent deformation or breakage.

• Hooke's Law is only applicable within the elastic limit because it is based on temperature variations

• Hooke's Law is only applicable within the elastic limit because it is a suggestion, not a rule