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Science 7 sf
structures and forces
Question | Answer |
---|---|
What is a natural structure? | is not made by people, occur naturally in the environment |
What is a manufactured structure? | is built by people, many are modelled after natural structures |
Whats a mass structure? | can be made by, piling up or forming similar materials into a particular shape or design. |
Whats a frame structure? | have a skeleton of strong materials, which is then filled and covered with other materials, supporting the overall structure |
What are aesthetics ? | are the study of beauty in nature. |
What are composite materials? | to enable the structure to withstand both types of forces acting on it, a composite material is used. |
What are moblie joints? | alow movement. |
What is weight? | is a force and should properly be measured in newtons is the force with which gravity pulls on an object. |
What is mass? | is the amount of matter an object is made of and weight is the force with which gravity pulls on an object. |
What is force? | is a push or pull on an object. Force is also weighed in newtons. |
What is tension force? | stretch a material by pulling its ends apart |
What is Shear force? | bend or tear a material by pressing different parts in opposite directions at the same time. |
What is compression force? | crush a material by squeezing it together. |
What is torsion forces? | twist a material by turning the ends in opposite directions. |
What is bending forces? | is a combination of tension and compression |
How do materials fail? | They Bend, Buckle,Torsion, or Shear |
What is Shear? | is a minor weaknesses in a material shear can cause failure because the particles move farther apart and are less attracted to each other |
What is bend or buckle? | can also cause a material to bend and buckle - like a can that is stepped on. To prevent this reinforcements - stringers and ribs - are used to strengthen the structure |
What is torsion? | can cause material failure. When sections of the structure slide past each other the structure can crack or break in two |