©BRAINBARTER EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
BME 214 Exam 1 Study Guide.
Tensile Stress - answer✔pulling force
Compressive Stress - answer✔pushing force
Stress (how to calculate) - answer✔F/A
F = force
A = cross sectional area
Units N/m^2 = Pa
Strain - answer✔deformation caused by applied stress
Epsilon = delta L / L (dimensionless)
L = original length
delta L = change in length
Stress-Strain Curve - answer✔slope of the curve is a measure of STIFFNESS
k or E = stress/strain = sigma/epsilon
aka Elastic Modulus/Young's Modulus
1|Page
, ©BRAINBARTER EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
Stress-Strain Curve:
Elastic Region
Plastic Region - answer✔Elastic Region: item will return to original shape after deformation
Plastic Region: item changes shape permanently after deformation
Tendon Equations - answer✔F = k (delta L)
Elastic Energy = 0.5 k (delta L)^2
Elastic Energy = 1/2 F (delta L)
k = EA/L
E = elastic modulus = stress/strain ~1.5E9 for tendon
stress = F/A
strain = delta L / L
10,000 cm^2 = 1 m^2
Safety Factor - answer✔strength/ typical load
Energy - answer✔energy stored/ put in when a stress is applied is proportional to the area
under the curve
viscoelastic material - answer✔only recovers a portion of the energy input
perfect elastic material - answer✔would recover all of the energy input
2|Page
ALL RIGHTS RESERVED.
BME 214 Exam 1 Study Guide.
Tensile Stress - answer✔pulling force
Compressive Stress - answer✔pushing force
Stress (how to calculate) - answer✔F/A
F = force
A = cross sectional area
Units N/m^2 = Pa
Strain - answer✔deformation caused by applied stress
Epsilon = delta L / L (dimensionless)
L = original length
delta L = change in length
Stress-Strain Curve - answer✔slope of the curve is a measure of STIFFNESS
k or E = stress/strain = sigma/epsilon
aka Elastic Modulus/Young's Modulus
1|Page
, ©BRAINBARTER EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
Stress-Strain Curve:
Elastic Region
Plastic Region - answer✔Elastic Region: item will return to original shape after deformation
Plastic Region: item changes shape permanently after deformation
Tendon Equations - answer✔F = k (delta L)
Elastic Energy = 0.5 k (delta L)^2
Elastic Energy = 1/2 F (delta L)
k = EA/L
E = elastic modulus = stress/strain ~1.5E9 for tendon
stress = F/A
strain = delta L / L
10,000 cm^2 = 1 m^2
Safety Factor - answer✔strength/ typical load
Energy - answer✔energy stored/ put in when a stress is applied is proportional to the area
under the curve
viscoelastic material - answer✔only recovers a portion of the energy input
perfect elastic material - answer✔would recover all of the energy input
2|Page
