The Effects of Loading
Mechanical Stress Concerned with the HOW force is distributed –
Force divided by area over which it acts (same units as PRESSURE – BUT pressure represents force distribution external to a body, Stress is the resulting force distribution INSIDE a body subjected to an external force.
PIC HERE pressure vs stress and stress strain graph
Mechanical Strain Amount of deformation of a structure divided by its original length or its original angular orientation. STRAIN = RELATIVE DEFORMATION
A STIFF object has greater COMPRESSIVE strength
A more ELASTIC/FLEXIBLE object has greater TENSILE strength
AFTER this add slides of loads on shoulder, elbow, hip etc.