Science unit 4 topic 1-4 Flashcards
function of a structure
what a structure is made to do. Eg;Transport
margin of safety
Building something that is safe and will be for a long time
How do you choose a material
Based on the structures function
Composite Materials
made with several different materials good for serving multiple purposes
Layered materials
different materials layered and stuck together.have different materials more useful with different functions. Eg;windshield
woven materials
fibres are woven interlocked making it flexible. EG;shirt
what is mass
how much matter is in something
force
a push or pull on an object
weight
force of gravity put on a mass measured in newtons
How do you measure mass
in kilograms using a balance scale ( to get from grams to kg divide by 1000)
what is used to measure force
Newtons using a spring scale
Convert mass to force
Kg to Newtons= kgx10
External forces
A force acting on the outside eg;wind
Internal forces
a force that acts on the inside eg;lungs
dead load
a permanent force eg;the weight of the structure it’self
Live load
a force that comes and goes eg;wind
Tension force
Stretch a material.tensile strength is the longest an object can handle before breaking
Compression force
squeeze a material together.Compressive is how long a material goes before losing shape or breaking
Shear force
bend or tear a material by pulling it in opposite in different directions.Shear strength how much shear force a material can stand before ripping
torsion force
twisting a material.Torsion strength the most torsion force a material can take and still spring back to it’s original shape
Steel tensile strength
particles pull together and need a lot of force to break it
