Exam 2 Flashcards
Float glass
Made by heating soda like glass while it floats on molten tin
Soda-lime glass
Fused silica
High melting point
Not for glass blowing, difficult to work with
Windows, light bulbs
Borosilicate
Silica + 5% boric oxide
Resistant to rapid temperature changes
Pyrex dishes, lab ware, thermometers, cookware, sealed-beam headlights
Tempered glass
Made with rapid heating and cooling to strengthen
Shatters into cubes
Car side windows, shower doors, phone screens, low windows
Laminated glass
Sheet of plastic sandwiched by glass
Car windshields
Transition lens glass
Contains particles of silver halide
Oxidation reduction reaction
Lightens or darkens with exposure to UV light
Crystalline solid
Structured molecules
Amorphous solid
Unstructured molecules
Looks like a solid
Acts like a liquid
Annealing
Slow cooling of glass so it doesn’t break
Concentric fracture
Fracture pattern where there are concentric circles around the hole
Radial fracture
The crack lines emanating from the center of the bullet hole in glass
Refraction
How a substance bends light — how fast light travels through the substance
Refractive index
How fast light travels though a material and that materials ability to bend the light
The known numbers of different substance’s refraction
Immersion method
Submerging glass into different oils with known refractive indexes and determining the refractive index of the glass based on that
Relief
The degree to which a mineral grain(s) appear to stand out from the mounting material
Strong: mineral stands out strongly from the oil
Moderate relief: mineral is still visible but less so
Low: mineral is basically invisible
Becke Line
Halo on the inside/outside edge of the glass
Wherever the halo is, that’s the substance with the higher index
Flax
Plant fiber
Oldest cultivated
Linen
Cotton
Plant
Most prevalent
Jupe
Plant
2nd most important (burlap)
Hemp
Plant
Source of 1st paper
Silk
Animal
Silkworm or spider
Rayon
Manufactured
Artificial [natural+chemical]
1st artificial fiber from wood
Most common artificial fiber
Acetate
Artificial from wood
Satin
Nylon
1st synthetic fiber [just chemicals]
The one we saw in that video
Acrylic
Synthetic wool
Polyester
Most common synthetic fiber
How do you differentiate between natural and synthetic fibers?
Burn them.
Natural: ash
Synthetic: melts
Plasma
Mostly water
Contains blood clotting elements
3 types of formed elements in blood
Red blood cells
White blood cells
Platelets
Antigen
Markers on cell surface
Triggers immune response
Antibody
Found in the serum
A protein that destroys/inactivates a specific antigen (clots blood)
Blood types
Type A (anti-B antibodies)
Type B (anti-A antibodies)
Type AB (no antibodies)
Type O (both antibodies)
Agglutination
Clumping or clotting of the blood due to the antibodies binding to the antigens on RBCs
Universal donor
Type O
Universal recipient
Type AB
Blood spatter
Blood drops form different shapes depending on…
- height it came from
- velocity
- angle of impact
- type of surface it hits
Area of convergence
Where the blood spatter originated from
Angle of impact
Angle at which a blood drop strikes a surface
Factors that affect blood spatter
- speed (faster—larger diameter)
- height (higher—larger diameter)
- volume (depends on the object blood originated from. Needle—small, baseball bat—large)
Refractive index formulas
Snell’s law: N1sin∆1=N2sin∆2
N1: 1st refractive index
N2: 2nd refractive index
∆1: angle of incidence
∆2: refractive angle
Index of refraction: N=C/V
Angle of impact calculation
Impact angle X = sin-1 width/length
