(C2) Materials in Domestic and Industrial Applications Flashcards
What is Hooke’s Law?
The force needed to extend or compress a spring
Equation of Hooke’s Law
F = kΔx
In Hooke’s law what is the relationship between force and extension of the spring?
Force is proportional to the extension of the spring
F ∝ x
Equation for Stress
Stress = force / cross-sectional area
What is the unit for stress?
Pa or N m⁻²
Equation for Strain
Strain = extension / original length
What is the unit for strain?
Strain has no units because it is a ratio of lengths, it is often expressed as a percentage
What is the elastic region?
Where elastic deformation occurs
What is the plastic region?
Where plastic deformation occurs
What is Young’s Modulus?
How easy a material can stretch
Equation for Young’s Modulus
YM = stress / strain
What is a ductile material?
A material that can be stretched into a wire without breaking
What is a malleable material?
A material that can be hammered into a shape
What is elastic deformation?
When a force is removed from a material it will return to its original shape, this is reversible
What is plastic deformation?
When a force is removed from a material it will not return to its original shape, this is irreversible
What is tension?
A force that causes the extension of a material
What is compression?
When a load applied to a material squashes it
What is ultimate tensile strength (UTS)?
The highest stress a material can take
What is creep?
A slower version of a plastic deformation which increases with temperature and can lead to failure
What is the strength of a material?
The ability of a material to withstand an applied load without plastic deformation
What is fatigue?
The weakening of a material caused by repeatedly applied loads
What is elastic hysteresis and why does it make loading and unloading follow different paths on a graph?
The stretching produces an increase in temperature(loading), but when the strain is reduced(unloading) the temperature drops.
Equation for Density
Density = Mass / Volume
