Take notes on page 108

 Different characteristics of tires can help identify a specific brand and narrow down the suspect pool ◦ Ridges – elevated regions of tires (also known as ribs) ◦ Grooves – indentations on tires ◦ Tire width ◦ Unique characteristics: imperfections in tread patterns due to wear and tear, pebbles embedded in grooves ◦ Angle of tread pattern

 How many ridges? ◦5◦5  Centered or off- centered? ◦ Centered

 Multiple vehicles could have the same type of tire; track width and wheelbase narrow down the search  Track width – measured from the center of each tire to the center of the opposite tire (need to measure front and rear)  Wheelbase – distance between the center of the front axle and the center of the rear axle

 Which letter represents front track width?  Which letter represents rear track width?  Which letter represents wheelbase?

 A measure of how tight a circle can be driven by a vehicle  The minimal amount of space required for a car to make a U-turn  During a sharp turn, the front outer tire creates a track because of additional stress  Helps determine size of vehicle (longer turning diameter, longer wheelbase, longer vehicle)

 Which vehicle has the most distance between front and rear tires?  What is this distance called?  How does that vehicle’s turning diameter compare to the other vehicles?

 How do you determine which vehicle was at a crime scene if you can determine track width, wheelbase and turning diameter from skid marks? ◦ Database of automobile statistics by make and model Database of automobile statistics by make and model ◦ Look up wheelbase and turning diameter to locate make and model of vehicle

 How are these factors going to affect tread patterns on tires? ◦ Under inflated tires ◦ Unbalanced tires ◦ Worn tires ◦ Damaged tires