Materials Flashcards
Define density
Mass per unit volume
What is hookes law?
The force needed to stretch a spring is directly proportional to the extension of the spring from its natural length, up to the limit of proportionality
What is the limit of proportionality?
The point beyond which the force on a spring is no longer proportional to the extension
What is the elastic limit?
The point beyond which a material suffers plastic deformation
What is meant by plastic deformation?
The permanent deformation or extension of a material
What does the gradient of a force against extension graph represent?
The spring constant
How do the areas under stress-strain graphs differ from the areas under force-extension graphs?
They are energies per unit volume
What is tensile force?
A force that stretches an object
What is a compressive force?
A force that compresses an object
How can the Young’s modulus be found from an stress-strain graph?
The gradient of the straight line section
How can the Young’s modulus be found from a stress-strain graph?
The gradient of the straight line section
Define yield strength
The force per unit area at which the strain increases considerably for a no, or little increase in stress
What is the UTS?
The ultimate tensile strength, the max stress a material can withstand
What is the density of water?
1000kgm^-3
What happens to the spring constant of 2 identical springs in series?
Halves
