Deck 15: Glass Evidence

Question 1

Density of glass is calculated by dividing the:

A)substance of a mass by its volume.
B)mass of a substance by its volume.
C)volume of a mass by its substance.
D)volume of a substance by its mass.

Answer 1

B

Question 2

As a bullet passes through glass, it pushes some glass ahead of it, causing a cone-shaped piece of glass to exit along with the bullet.The cone of glass makes the exit hole:

A)larger than the entrance hole of the bullet.
B)smaller than the entrance hole of the bullet.
C)the same size as the entrance hole of the bullet.
D)None of these choices.

Answer 2

A

Question 3

Glass will break first on the weaker side, the side:

A)opposite the strike.Radial fractures will result.
B)of the strike.Radial fractures will result.
C)opposite the strike.Tertiary fractures will result.
D)of the strike.Tertiary fractures will result.

Answer 3

A

Question 4

If several shots are fired through glass, the ___________________________ in which the shots were fired can be determined if enough of the glass is available or can be reconstructed.

Question 5

Fine glassware and decorative art glass, called crystal or leaded glass, contain lead oxide rather than calcium oxide.

Question 6

Silicon dioxide is:

A)the chemical name for silica.
B)the chemical name for glass.
C)the chemical name for obsidian.
D)None of these choices.

Question 7

Refractive index comparisons result in circumstantial class evidence and:

A)can confirm guilt.
B)cannot to confirm guilt.
C)only provides meaningful results for window glass or television glass.
D)only provides meaningful results for quartz glass or leaded glass.

Question 8

The primary ingredient of glass is carbon dioxide.

Question 9

When glass is hit:

A)it cannot stretch.
B)it can stretch a great deal.
C)it can stretch slightly.
D)it cannot stretch unless it is heated.

Question 10

Glass is a hard, amorphous material made by melting silicon dioxide, calcium oxide, and sodium oxide at very high temperatures.

Question 11

Each type of glass has a density that is specific to that glass.One method of matching glass fragments is by a density comparison.

Question 12

If the refractive index of the liquid medium is different than the refractive index of the piece of glass, a halo-like ring appears around the edge of the glass.This halo-like effect is called a:

A)Becke line.
B)Becke edge.
C)Beck line.
D)Beck edge.

Question 13

Light travels:

A)nearly as fast through air as it does through a vacuum.
B)nearly as fast through a vacuum as it does through air.
C)at the same speed in both air and water.
D)at the same speed in methanol and clove oil.
E)​in a way that varies on a case-by-case basis based on environmental factors.

Question 14

The refractive index is a measure of how light bends as it passes through:

A)three or more substances.
B)one substance and into another.
C)four or more substances.
D)None of these choices.

Question 15

The submersion method involves placing the glass fragment into different liquids of known refractive indexes.If a piece of glass and a liquid have the same refractive index, the glass fragment will seem:

A)larger when placed in the liquid.
B)smaller when placed in the liquid.
C)to disappear when placed in the liquid.
D)to reappear when placed in the liquid.

Question 16

If the refractive indexes of several different liquids are known, the:

A)submersion method can be used to estimate the refractive index of the glass.
B)submersion method can be used to estimate the reflective index of the glass.
C)reflective method can be used to estimate the refractive index of the glass.
D)reflective method can be used to estimate the submersion index of the glass.

Question 17

There is sophisticated technology that enables nondestructive analysis of glass.Which of these technologies can help determine the cause of an automotive collision by determining whether the headlights were on at the time of the collision?

A)scanning electron microscopy (SEM)
B)X-ray fluorescence (XRF)
C)inductively coupled plasma-mass spectrometry (ICP-MS)
D)None of these choices.
E)​All of these choices.

Question 18

The speed of an object when it hits a piece of glass influences the number and location of concentric circles in the fracture pattern.An object moving at high speed upon impact, such as the bullet, produces:

A)concentric circles with wide margins.
B)concentric circles with narrow margins.
C)tighter concentric circles.
D)widely spaced concentric circles.

Question 19

Glass is called an amorphous solid because its atoms are arranged in a random fashion.

Question 20

One method of determining if the evidence glass matches the glass from the crime scene is to compare the:

A)index of the evidence glass to the index of the glass from the crime scene.
B)refractive index of the evidence glass to the refractive index of the glass from the crime scene.
C)reflective index of the evidence glass to the reflective index of the glass from the crime scene.
D)None of these choices.

Question 21

________________________________________is also known as tempered glass.It is used in car windows, shower doors, and glass tables.As it has been subjected to extreme temperatures or chemical treatments, it has improved strength.

Question 22

____________________________________ is a combination of two or more types of glass, one hard and one soft.The softer layer makes the glass more elastic so it can flex instead of shatter.

Question 23

The angle at which a bullet enters a piece of window glass can help locate the position of the shooter.If the bullet was fired perpendicular to the windowpane, the entry hole of the bullet will be _______________________.

Question 24

A high-velocity bullet fired from a great distance will often exhibit characteristics of a ____________________________________ fired from a closer range.