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Webquest Review. Please have your paper from last class out and perhaps even a loose leaf paper. Internal and External Forces . Webquest Review. FORCES. Remember that a FORCE is a stress such as a push or pull that could change a structures shape or size . Internal Forces .
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Webquest Review Please have your paper from last class out and perhaps even a loose leaf paper.
Internal and External Forces Webquest Review
FORCES • Remember that a FORCE is a stress such as a push or pull that could change a structures shape or size
Internal Forces • Internal Forces: stresseswithin materials from which the material is made.
Compression • Force that SQUEEZES a materials together • Tends to become shorter • Compressive strength= • Examples of where we see compression?
Tension • Force that STRETCHES materials apart • Tends to become longer • Tensile Strength • Examples of where we see tension?
Bending • When straight material becomes CURVED • Once side squeezes together and one side stretches apart • Examples where we see bending?
Shearing • Force that’s causes parts of material to SLIDE past each other in opposite directions • Shear strength = • Examples of where we see shearing?
Torsion • Action that TWISTS materials • Torsion strength = • Examples of where we see torsion?
LOADS • REMEMBER LOADS ARE FORCES THAT ACT ON STRUCUTURES
External forces • External Forces: stresses that act on structures from outside it. These external forces produce Internal forces
Dead Load • Weight of a structure it self • Permanently attached to the structure • Columns, beams, nuts etc
Live Load • Weight of the stuff on the structure, move in or on a structure • People, furniture, cars etc May need to strengthen structures that experience live loads
Environmental Conditions • What were some ways you strengthened the structures?
Mr. Stronginsky • Volunteers to show work on board.
Making use of stress • BUCKLE: car bumpers, grass, cardboard box flaps • Buckle in a crash so people are not injured • SHEAR: gear shafts, propellers in boats • Shear pin • Gears slip past each other • TWIST: twisting yarn as opposed to straight fibers • controlled twisting turns hair into braids, string into ropes, and wires in to cables