1. CMGT 322 LECTURE 2

2. FORCES  DEFINE FORCE  DEFINE UNITS FOR FORCES  THREE IMPORTANT FACOR ABOUT FORCES: MAGNITUDE, DIRECTION, SENSE  STRESS= FORCE/AREA  UNITS FOR STRESS

3. LECTURE TWO  TYPES OF STRESS  COMPRESSIVE  TENSILE  SHEAR STREE  STRESS IS RELATED TO FORCE DIVIDED BY THE AREA

4. LECTURE TWO  COMPRESSIVE STRESS ISSUES  TENSILE STRESS ISSUES  SHEAR STRESS ISSUES  STRAIN=e/L  STRESS IS DIRECTLY PROPORSIONAL TO STRAIN

5. LECTURE TWO  MODULUS OF ELASTICITY=STRESS/STRAIN  Es= 30,000,000 psi  Ew= 1.0-2.5 million psi  Ec= 2-5 million psi  It is important to know how stiff the material is, modulus of elasiticity

6. Lecture two  Five variables we need to deal with when it comes to stress strain and modulus of elasticity: –LENGTH –FORCE/LOAD –AREA –ELONGATION –MODULUS OF ELASTICITY

7. LECTURE TWO  CROSS SECTION ARE IS VEY IMPORTANT, WE NEED TO KNOW HOW TO CALCULATE IT  WATCH UNITS  SEE EXAMPLES