What is thermal stress caused by?
A Change in temperature
B Applied external force
C Material’s internal friction
D Material elasticity
What does the stress-strain curve represent?
A Force vs. energy
B Material’s elasticity and deformation
C Temperature vs. strain
D Energy vs. force
What is the primary cause of fatigue failure?
A High temperature
B Static loads
C Cyclic loading
D Rapid impact
What is creep in materials?
A Instantaneous fracture after loading
B Slow deformation under constant stress
C Fast fracture under stress
D Sudden deformation due to temperature change
What does the failure theory predict?
A Material’s temperature range
B Material’s deformation
C Material’s strength
D Material’s fracture under stress
What is the significance of the yield point?
A Point where permanent deformation begins
B Point of maximum stress
C Point of fracture
D Point of elasticity
What is the characteristic of a brittle material?
A Sudden fracture without plastic deformation
B High toughness
C High elasticity
D Ability to absorb large energy before failure
How is tensile stress measured in materials?
A By compressive force
B By applied load divided by area
C By elongation
D By internal energy
What does shear stress cause in materials?
A Compression
B Lateral deformation or slippage
C Stretching along the length
D Twisting of the material
What does a material’s toughness measure?
A Ability to deform without breaking
B Resistance to corrosion
C Ability to resist temperature changes
D Ability to resist indentation
What is the primary characteristic of a ductile material?
A Ability to absorb high energy before fracture
B High resistance to fracture
C Ability to undergo permanent deformation
D Low elongation before fracture
What happens during plastic deformation?
A The material becomes stronger
B The material returns to its original shape
C The material fractures immediately
D The material deforms permanently
What is the effect of temperature on thermal stress?
A It increases material toughness
B It creates internal stresses in constrained materials
C It causes uniform contraction
D It causes uniform expansion
What is the relationship between stress and strain in the elastic region?
A Proportional
B Inversely proportional
C Exponentially related
D No relation
How is the maximum shear stress calculated?
A By dividing the total stress by area
B By taking the square root of the sum of squares of normal stresses
C By finding the difference between normal stresses
D By using the formula σ = Eϵ