Materials Flashcards
What is hooke’s law?
And what is Hooke’s law equation?
The extension is proportional to the force applied provided the limit of proportionality is it exceeded.
F=kx
If one spring is stretched by 1 meter when 1 newton of force is applied, how far would two springs in parallel stretch under 1 newton of force?
And what equation can be used for this?
Half a metre
(1/k)+(1/k)= 1/K
If one spring is stretched by 1 meter when 1 newton of force is applied, how far would two springs attaches end to end stretch under 1 newton of force?
2 metres
k+k=K
What is the energy conversion of a mass stretching a spring?
Gravitational potential to storage potential
The area under a force extension graph is what?
Equal to the potential energy storage in the object extending
What is the symbol for stress and strain?
Stress: σ
Strain: ε
What is the letter for Young’s modulus?
E
Something that can withstand high stress but doesn’t strain much before breaking is what?
Brittle
Crunchie
A material that can undergo large amounts of strain but little stress is what?
Polymeric
Wham
A material that stress and strains evenly (ish) until it reaches a region of plastic deformation where it strains until it breaks
Ductile
When stretching a rubber band what does the stress strain graph look like when loading and unloading with masses?
When loading the gradient starts larger, gets smaller the gets larger again.
When unloading a similar path is taken in reverse slighting below the loading graph, but ending and starting at the same points
What does the area enclosed in a hysteresis loop equal to?
The energy transferred per unit volume from elastic potential is heat energy
Define ductile
A material that has a large plastic region in a stress strain graph
Define Brittle
Does not show plastic deformation and deforms little under high stress
