Forensic Glass Analysis

The bright halo that appears near the border of a glass particle that is immersed in a liquid of a different refractive index is called the:

• border line
• refractive line
• Becke line
• immersion line

A crack in glass that moves outward from the point of impact like spokes on a wheel is called a:

• compound fracture
• concentric fracture
• spoke fracture
• radial fracture

Which type of fracture is shown by letter B?

• radial
• concentric
• birefrigent
• none of these

Which of these applies to tempered glass?

• it is made by rapid heating and cooling
• it shatters into oval shaped pebbles
• it is used for cookware, tub enclosures, and coffee pots
• all of these describe tempered glass

Which type of glass is used to make car windshields?

• tempered
• laminated
• acrylic
• standard

In the lab, a Pyrex/borosilicate piece of glass was dipped in vegetable oil and disappeared from view. What does this tell us?

• the piece disintegrated in the oil
• the oil and the glass had the same refractive index
• the oil and the glass chemically reacted
• the oil and the glass have different refractive indices

Because glass is a solid with random arrangement of motionless atoms, it is called:

• plasma
• obtuse
• amorphous
• frozen

You can tell what side of a glass piece was struck by observing:

• the horizontal waves

• the right angle rule

• the becke lines

• the refractive index

Glass evidence is:

• class 
• individual 
• direct
• both class and individual

Glass density can be determined by:

• dividing the mass in grams of the glass by the water it displaces in mL 
• measuring the thickness of the glass with a cm ruler
• hitting the glass with a hammer to see the fracture patterns
• all of these