The Centre of Gravity of a Structure
What is the centre of gravity?
The centre of gravity is the point where all of an object's weight is evenly distributed.
Gravity pulls ________ while a table pushes ____ to keep it stable.
Gravity pulls down while a table pushes up to keep it stable.
These structures have very little empty space.
Solid structures
Symmetry happens when once side ________________ the other, like a reflections.
Symmetry happens when once side mirrors the other, like a reflections.
Tall, uneven structures have a __________ centre of gravity, making them more likely to _____________.
Tall, uneven structures have a higher centre of gravity, making them more likely to topple.
Carrying a heavy backpack does this to your centre of gravity?
Carrying a heavy backpack shifts your centre of gravity.
This forces refers to how strong a force is, and is measured in newtons (N).
Magnitude
___________ structures refer to structures made up of a skeleton or frame.
Frame structures
___________ is when the right and left sides are identical.
Bilateral is when the right and left sides are identical.
This structure in San Francisco uses symmetry in its towers and cables to handle fores such as wind and tension.
The Golden Gate Bridge
If the centre of gravity moves __________ the base of support, the structure becomes _________.
If the centre of gravity moves outside the base of support, the structure becomes unstable.
The ___________________ is the surface or area where the force is acting.
plane of application
Frame structures are ________ because of _____________ inside.
Frame structures are lightweight because of lots of empty space.
Radial symmetry occurs when the structure is symmetrical ________________________.
Radial symmetry occurs when the structure is symmetrical around a central point.
Solid structures rely on this to hold their shape and provide strength.
Skyscrapers are designed with ____________ to keep their centres of gravity low and stable.
Wide Foundations
This is what it's called where the force is applied on a structure.
Point of Application
Frame structures use beams, columns, or trusses to do this...
Distribute forces evenly.
This dome in Rome is an example of radial symmetry.
Examples of shell structures include....
bottles,eggs, sports domes
The centre of gravity of a playground _________________ is located at the _________________point.
The centre of gravity of a playground seesawis located at the pivot point.
The magnitude of force on a bridge comes from......
the weight of cars, trucks, and pedestrians
Shell structures are ___________ but strong because of their shape.
Shell structures are thin but strong because of their shape.
Symmetry helps balance structures, making them _____________ and more ____________.
Symmetry helps balance structures, making them stronger and more stable.
The symmetrical roof design of the ____________________ helps with even ____________________.
The symmetrical roof design of the Sydney Opera House helps with even weight distribution.