Nonmetals In The Plant Flashcards
A liquid has a fixed volume but it’s shape can change
True
The density of a liquid is measured in
Mass unit per unit of volume. In the us we use lb/ft^3
Water 62.4
Evaporation is a form of what?
It is a form of vaporization. During evaporation, molecules with enough energy escape from the surface of the liquid evaporation and it is also a cooling process
How is density (mass per unit of vol.) measured in gases?
It is measured in fractions of a pound per cubic foot.
What is laminar flow?
Laminar flow is when a fluid moves in layers parallel to the pipe
Can gasses dissolve in liquids?
Yes they can but the solubility decreases as the temperature rises. This solubility is usually 0 at the boiling point of the liquid.
Describe thermoplastics.
Thermoplastics soften when heated and harden when cooled, they can be reheated and reshaped many times
In regards to molding plastics what is one of the most widely used processes?
Injection molding is the most widely used. It is high speed and low cost for forming intricate parts.
What is filament winding in regards to reinforcing plastic?
Filament winding is used on tanks and containers that require high strength and are resist to corrosion. A continuous strand of resin coated glass fibers wound around a special form called a mandrel.
How should you drill in plastics?
You should drill for short periods of time to allow the part to cool. To avoid chipping and cracking reduce the feed rate just before the drill point penetrates the other side.
What should you do when reinforcing, coating, or patching corroded surfaces on plastic.
Remove as much as the damaged area as possible. Use a sanding disk to remove rough material. Clean both sides of the material with solvent to remove oils and dirt
Elastomers have the ability to be stretched to least _______ their original length and then _______________.
Twice
Return rapidly to its original shape.
What class of rubber resists damage by extreme high and low temperatures.
Class T rubbers
Most rubber compounds can burn.
True
Describe vulcanizing and the products that come from it.
The process of adding sulfur to rubber and then heated. The more sulfur added the harder the rubber. Soft rubber has less than 4% sulfur
Which rubber insulation cables do you certainly want to have flexibility?
Extension cords, welding cable, and power tool cords
What is a radial cut for lumber?
A radial cut is produced by cutting a log lengthwise, with the cut going through or near the centerline of the log.