Glass Fractures
Answer Blog for Quiz on Glass Fractures
Quiz Crafted by - Ms. Neha Jain
(Senior Scientific Officer)
Sherlock Institute of Forensic Science India Pvt. Ltd, New Delhi
Introduction to Glass Fractures
Glass is a hard, amorphous solid. Glass fragments may be evidence of great value encountered in the investigation of various types of offenses. At the scene of occurrence, the glass may be fractured either as an intentional act or due to an accident. Glass fractures are of paramount importance in shooting cases where the firearm is used as it can provide significant information related to the occurrence and facilitates a variety of evaluations. In fact, fractography i.e. analysis of fracture patterns is the means and method for characterization of fractured units or fragments in order to study or identify the mechanism of such fractures. The study of fracture patterns of glass has been of long interest to the forensic community. The glass fracture pattern analysis is very useful to establish the sequence of events and link together items of evidence and it is of paramount importance in such cases where the firearm is used.
Let's look at the questions and their answer.
1. The fracture formed radially at right angle on the reverse side of the impact is termed as?
a) Concentric Fractures
b) Radial Fractures
c) Heat Fractures
d) Both (a) and (b)
Answer – b) Radial Fractures
2. The fracture pattern that appears in the form of wavy irregular lines without any indication of the point of origin is?
a) Stress Marks
b) Cone Fractures
c) Heat Fractures
d) Radial Fractures
Answer – c) Heat Fractures
3. Cracks which appeared in the form of spider web and connects two radial cracks, arises from one radial crack to another from the loaded side to unloaded side is known as?
a) Stress Marks
b) Concentric Fractures
c) Heat Fractures
d) Radial Fractures
Answer – b) Concentric Fractures
4. The breakage pattern appeared by the shot of a bullet comprises both radial as well as concentric fractures with a formation of a hole at the center is?
a) Concentric Fractures
b) Heat Fractures
c) Radial Fractures
d) Cone Fractures
Answer – d) Cone Fractures
5. Out of the following which fracture pattern extends to the glass edge like spokes in a tire of a bicycle?
a) Concentric Fractures
b) Heat Fractures
c) Radial Fractures
d) Cone Fractures
Answer – c) Radial Fractures
6. Which of the following fracture of glass results in the formation of an irregular oval shaped hole on the exit side?
a) Stress Marks
b) Cone Fractures
c) Heat Fractures
d) Radial Fractures
Answer – b) Cone Fractures
7. The concentric cracks which appear from the loaded side to the unloaded side and connect two radial cracks are termed as?
a) Tangential Cracks
b) Hackle Marks
c) Heat Fractures
d) V shaped Cracks
Answer – a) Tangential Cracks
8. The fracture patterns that consist of coarse marks which are parallel to one another and also to the direction of propagation of fracture are termed as?
a) Stress Marks
b) Concentric Fractures
c) Hackle Marks
d) Both (a) and (c)
Answer – d) Both (a) and (c)
9. Which fracture pattern appear on the same side of the force of impact?
a) Hackle Marks
b) Heat Fractures
c) Concentric Fractures
d) Radial Fractures
Answer – c) Concentric Fractures
11. The first fracture pattern or primary pattern appeared on breakage to any glass surface is?
a) Rib Marks
b) Cone Fracture
c) Radial Fracture
d) Circular Cracks
Answer – c) Radial Fractures