Materials Flashcards
What is the equation for density?
density = mass/ volume
What is Hooke’s law?
F=kE
What is meant by the elastic limit?
the point beyond which the behaviour of the material changes irreversibly. it has been deformed plastically
What is meant by elastic deformation?
when a material is stretched by a force but will return to its original length/state when the force is removed. it obeys Hooke’s law
What is meant by plastic deformation?
when a material has had a force applied to it so that it has passed its elastic limit and will not return to its original state
How would a material which breaks easily be described?
brittle
What is meant by elastic strain energy?
the energy stored in a material as it extends when a force is applied.
E = 0.5F x change in L
How do you calculate tensile strain?
strain = extension / initial length
How do you calculate tensile stress?
stress = Force / cross sectional area
How do you calculate Young’s modulus?
Stress / strain
Would a stiff material have a higher or lower Young’s modulus than a flexible one?
higher
