Jeopardy Fiber types Character -istics TestingMisc. Other review Q $100 Q $200 Q $300 Q $400 Q $500 Q $100 Q $200 Q $300 Q $400 Q $500 Final Jeopardy.

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Presentation transcript:

Jeopardy Fiber types Character -istics TestingMisc. Other review Q $100 Q $200 Q $300 Q $400 Q $500 Q $100 Q $200 Q $300 Q $400 Q $500 Final Jeopardy

$100 Question from H1 What are three different sources of natural fibers?

$100 Answer from H1 Plants, animals and mineral

$200 Question from H1 Why do animal textiles shed easily?

$200 Answer from H1 They tend to be loosely spun to make them more comfortable.

$300 Question from H1 A fiber is analyzed and found to be made of protein. Give an example of what type of fiber this could be.

$300 Answer from H1 Any animal fiber: wool, angora, cashmere, etc.

$400 Question from H1 What four plant parts are common sources of fibers?

$400 Answer from H1 Stem, leaves, seeds, and fruit.

$500 Question from H1 Give an example of a mineral fiber and its use.

$500 Answer from H1 Asbestos: home siding, shingles, fire resistant clothing Fiberglass: home insulation

$100 Question from H2 Fibers may be amorphous or crystalline. Which type tend to be soft, elastic, and absorbent?

$100 Answer from H2 Amorphous

$200 Question from H2 Qualities of synthetic fibers may vary greatly due to two characteristics of the spinneret. What are these two characteristics?

$200 Answer from H2 Size and shape

$300 Question from H2 List three characteristics of fibers that you might see under a microscope.

$300 Answer from H2 Shape, Cross-section color, clear or translucent, Solid or hollow, Pitted on surface diameter

$400 Question from H2 Which type of fiber has the following characteristics? Natural or synthetic? *Melt at a high temperature *Damaged by microbes *Slow to deteriorate in light

$400 Answer from H2 Those are all properties of natural fibers.

$500 Question from H2 Look at the picture below. The small specks all over the fiber are bits of titanium dioxide. Why is this chemical added to fibers?

$500 Answer from H2 It was added as a delusterant in order to make the manmade fiber look less shiny.

$100 Question from H3 What is meant by a “destructive test?”

$100 Answer from H3 It is a test in which the fiber is destroyed. Burn analysis, gas chromatography, and solubility tests are all destructive.

$200 Question from H3 List three things to look for in a burn analysis that may help you identify the fiber.

$200 Answer from H3 Does it melt or curl? Does it keep burning or go out? Does it glow? Does it burn fast or slow? Is there black or white smoke? Is there black or white ash? Is the residue hard or squishy?

$300 Question from H3 What types of fibers smell like burnt hair when burned?

$300 Answer from H3 Any animal fibers like wool

$400 Question from H3 Under the microscope you can distinguish between natural and manmade fibers by….

$400 Answer from H3 The uniformity of color and smoothness of manmade fibers. Natural fibers in a yarn tend to look fuzzy. You may see a cuticle pattern with animal fibers.

$500 Question from H3 Most of the burn residue of fibers looks the same. What is different about cotton residue?

$500 Answer from H3 Most residue was black and crunchy. Cotton’s residue was white/gray and ashy.

$100 Question from H4 Give an example of secondary transfer.

$100 Answer from H4 A fiber from Jack’s carpet gets onto Jack. (direct transfer) The carpet fiber then is rubbed onto a stranger’s pantleg in the elevator. (secondary transfer)

$200 Question from H4 A rookie detective arrives at a crime scene and directs the CSI to just take one fiber found on the bed. Why is it important to collect more than one sample and to know how many fibers were there?

$200 Answer from H4 Fibers may vary from a single source. The number of fibers may indicate the type of crime or at least the intensity of the crime.

$300 Question from H4 What is a polymer and what is it made of?

$300 Answer from H4 A polymer is a long chain of repeating units. The repeating units are called monomers.

$400 Question from H4 Fibers may act like prisms. They can separate light into….

$400 Answer from H4 Its component wavelengths or colors to make a rainbow.

$500 Question from H4 List three ways you could collect fiber evidence from a crime scene.

$500 Answer from H4 Special vacuum Tape lift Hand pick with a tweezers or forceps

$100 Question from H5 What is the best way to safely extinguish a small tabletop fire?

$100 Answer from H5 Smother it with a fire blanket.

$200 Question from H5 Under what conditions must goggles be worn?

$200 Answer from H5 Fire, chemicals, and glassware

$300 Question from H5 Fiber evidence must be collected within 24 hours. Why? (list two reasons)

$300 Answer from H5 95% of the fibers will be gone after 24 hours and the crime scene will be contaminated with many extraneous fibers by then.

$400 Question from H5 What is the danger in using asbestos fibers?

$400 Answer from H5 They are essentially tiny glass-like fragments and when inhaled, they lodge in your lungs and cause inflammation. This may lead to cancer.

$500 Question from H5 A single white cotton fiber is found on a victim. The fiber is consistent with a suspect’s t-shirt. As the defense attorney, what will you say about this evidence?

$500 Answer from H5 A single white cotton fiber is class evidence. It is the most common type of fiber and could have come from numerous sources. Also, it may have gotten on the victim via secondary transfer from any other white cotton textile.

Final Jeopardy Describe a case study in which the fiber evidence was crucial to the conviction of a suspect.

Final Jeopardy Answer Answers may vary- e.g. Wayne Willliams (24 million to 1 chance that the fibers on the victim would match the fibers in Williams’ home)