Science

In science we finished up are forces and structures unit. In this unit we learned about the different types a structures,  the advantages and disadvantages of the structure types, force diagrams, internal and external forces, different types of bridges, and structural efficiency. The different types of structures we learned about were solid/mass, frame, and shell structures. Force diagrams are simple pictures using arrows to illustrated how forces are acting upon an object. The external forces are live load and dead loads.

The internal forces are compression, tension, torsion, and shear. The different types of bridges that we learned about were beam bridges, arch bridges, and suspension bridges. Structural efficiency is a relative number that compares the maximum amount of mass a material can hold divided by the mass of the structure itself. For example a bridge hold 200kg and it weighs 100g, first you convert 200kg into grams which would be  200 000g. Then you divide 200 000g by 100g, the structural efficiency is 2000.

By: Derek 7B