Fiber Analysis Exam with Verified Answers

Fiber - The smallest unit of a textile material that has a length many times greater than its diameter What affects the transfer of fibers and the significance of fiber association? - The type and length of fiber used, the type of spinning method, and the type of fabric construction How are fibers gathered at a crime scene? - With tweezers, tape, or a vacuum Where do fibers generally come from? - Clothing, wigs, carpeting, and blankets How can you differentiate between man-made fibers? - The likelihood of two or more manufacturers exactly duplicating all of the aspects of the textile is extremely remote/rare. What is the problem with fiber evidence? - Fibers are not unique, you cannot pinpoint an offender in any definitive manner, and there must be other factors involved Name and describe the five microscopes used to examine fibers (only describe first two) - 1.) Compound microscope- uses light reflected from the surface of a fiber 2.) Comparison microscope- two compound microscopes joined by an optical bridge; used for more precise identification 3.) Phase-contrast microscope 4.) Electron microscopes 5.) Scanning electron microscope Give three examples of animal, plant, and manufactured fibers and note which one is most common - Animal-wool, camel, and alpaca Plant-cotton, hemp, and flax Manufactured- polyester, rayon, and acetate The cross section of a man-made