3.4.2 Materials Flashcards
What is the formula for density and what are the units?
Density (kgm-3) = Mass (kg) / Volume (m3)
What is 1cm in ml?
1cm=1ml
What is 1ml in cm?
1ml=1cm
What is an alloy?
An alloy is a mixture of two or more metals
How do you work out the volume of a irregular solid?
Submerge it in water and the increase in level is equivalent to it’s volume
How do you work out the mass of a liquid?
The measurement of the mass of the liquid and container minus the mass of the same but empty container
What is 1kg equal to in g?
1kg=1000g
What is 1000g equal to kg?
1000g=1kg
What is 1m3 equal to in cm3?
1m3=10 power of 6 cm3
What is 10 to the power of 6cm3 equal to in m3 ?
10 power of 6 cm3=1m3
What is F=ke
Force = spring constant * extension
F k e
What is Hooke’s Law?
Hooke’s Law is the force applied to a body is proportional to the extension that it experiences up to the elastic limit (limit of proportionality)
When does Hooke’s Law only apply?
Hooke’s law only applies within the elastic region of a material (before the force permanently deforms it)
What does F∝e mean?
Force is directly proportional to the extension
F∝e
What are the 4 types of forces?
- Tensile
- Compressive
- Shear force
- Torsional force
When in a series, what is the spring constant?
In a series, the spring constant is less that that of 1 spring
1/k1 + 1/k2 = 1/kseries
When in a parallel, what is a spring constant?
When in a parallel, the spring constant is more than that of 1 spring
k1 + k2 = kparallel
What is elasticity?
Elasticity is the ability of an object to resume to its original shape after it has been deformed or distorted and the forces that deformed it has been released
What is plasticity?
Plasticity is being able to be shaped easily
What is the elastic limit?
The elastic limit is the maximum extent to which an object can be stretched without permanent alteration and will return to its original dimension after the applied stress is removed
What is stiffness?
Stiffness is the extent to which an object resists deformation in response to an applied force
What is ductility?
Ductility is when a solid object stretches under tensile stress
What is brittleness?
Brittleness is when subjected to stress, a material breaks without significant plastic deformation
What is the plastic region?
Plastic region is when an applied stress is so great, the material is unable to return to it’s original dimensions therefore it is permanently deformed
What are materials with no plastic region often?
Materials with no plastic region are often very brittle
What is mechanical stress?
Mechanical stress is when a stress applied to a material depends not only on the force applied but also the area to which it is applied - pressure felt by material
What is the symbol for stress?
σ
What is the equation for stress?
Stress(σ) = Force (F) / Area (A)
Nm-2 N m2