1.1 Material Seection Part 2 Flashcards
What physical properties do materials have?
Density, electrical, thermal conductivity.
What is mass?
Its the amount of matter in a set space.
How is the relative density of materials found?
By comparing it with the density of pure water at 4°C.
How can heat affect the size of a matterial.
It makes it expand but only by a slight amount
What is electrical conductivity?
It’s the movement of electricity through a material.
What are electrical insulators?
Materials that can resist the flow of electricity.
What are common conductors?
Metals - iron, copper, gold, brass
Liquids - water
What are common insulators?
Woods - Oak, Pine, Birch,
Plastics - Nylon, ABS, PVC, Urea Formaldehyde
Glass
What are semi-conductive material?
It’s a material that is conductive under certain conditions.
Such materials are Silicon & Germanium.
What is thermal conductivity?
The movement of heat energy through a material.
I got no clue,
Different materials have different thermal conductive properties.
What is the best insulator and how is it incorporated into products?
Air
There is an empty space left between 2 pieces of material and they are separated by air which acts as an insulator.
What effects does heat have on materials.
When they heat up the material expands and when it cools down it shrinks.
