4. Trace and Pattern Evidence

Hair And Fiber — Quiz

Test your understanding of hair and fiber with 5 practice questions.

Practice Questions

Question 1

During microspectrophotometric analysis of fiber color, an acceptance criterion requires peak wavelength agreement within ±2 nm. If the known fiber shows an absorbance peak at 620 nm and the questioned fiber at 623 nm, what is the appropriate conclusion?

Question 2

Under microscopic examination, a hair displays a crown‐like (coronal) scale pattern. This most likely indicates hair from:

Question 3

Three hair diameter measurements yield 68 µm, 72 µm, and 70 µm. What is the sample standard deviation (in µm)?

Question 4

A hair sample matches a brown hair color found in 30% of the relevant population. Using a simplified likelihood ratio approach, what is the LR if the hair color matches?

Question 5

An FTIR microspectrophotometry spectrum of a fiber shows strong absorption bands at approximately 3300 cm^{-1} (N–H stretch) and 1640 cm^{-1} (C=O stretch). Which fiber type is indicated?