Quiz 1.2 Flashcards
Internal rotation
Front of the body rotates toward the midline of the body. Similar to adduction
External rotation
Front of body rotates away from the midline of the body. Similar to abduction
Internal loading
Application of force, largely produced by muscles
Internal structures deformed due to external (mechanical) load
Ligament, tendon, cartilage, bone, muscle
Material properties describe the response of structure
Types of mechanical load
Uniaxial and Combined
Mechanical load creates mechanical stress
Uniaxial load
Load in 1 direction
Compression, tension, shear
Combined load
Load from multiple direction (multiaxial)
Multiple stresses and different magnitudes of stress at analysis plane
Bending
Torsion
Greater distance from axis the greater magnitude
Stress
Stress = force / SA
Units N/m^2 (pascal)
(Internal force per unit area which the force acts)
Allows us to compare elements of different shapes and sizes
Tension
Pulling or stretching force directed axially through a body
Acts Perp to analysis plane and analysis plane cuts structure perpendicularly through longest dimension
Compression
Pressing or squeezing force directed axially through body
Acts perp to analysis plane
Shear
Force directed parallel to a surface; causes a sliding of surfaces in opposite directions; acts parallel to analysis plane
Bending
Load applied to structure causing it to bend about a neutral axis
Compression and tension develop on opposite sides of axis; shear developed along axis
Types of bending
3- point bending
Cantilever bending
(see diagrams)
Torsion
Load producing twisting of a body around its longitudinal axis
Shear stress occurs parallel to axis
Compression and tension occur diagonal to axis
Think Indian rugburn
