There are several factors that can affect a person's reaction time while driving in an emergency situation: 1) Distractions like using a phone, eating, or interacting with passengers can slow a person's reaction time by taking their focus away from the road. 2) A person's state of alertness also impacts reaction time - being tired, drunk, or otherwise impaired can lengthen the time it takes to respond to hazards compared to being fully alert. 3) Individual physiological differences like age, health, genetics, and fatigue level can cause reaction times to vary between people even when fully alert. Maintaining alertness and avoiding unnecessary distractions can help ensure the fastest reaction time possible.

1. What Do You See?

2. What Do You Think? What factors affect the time you need to react to an emergency situation while driving? Begin a new page in your Active Physics log (lab book). Write “Section 1 Reaction Time” at the top of a new page. Don’t forget to add this page to your table of contents! Do it now!! Copy down the question. Record your ideas about this question in your log book.

3. Investigation 1.1 Materials Needed: stopwatch or cell phone timer meter stick lab book

4. Physics Talk - Crucial Physics A person has a measurable reaction time reaction time is affected by distractions reaction time without distractions is about 0.12 s this is the time it takes the nerve impulse to move from your eyes to your brain and then from your brain to your muscles Poor reaction time can lead to more accidents Driving under the influence of alcohol or other drugs (legal or illegal) is dangerous because of the effect these things have on reaction times

5. Physics Talk reaction time: the time needed to respond to a situation when you have advanced notice that you are going to need to respond, your reaction time is faster – in other words, when you are alert, you have a faster reaction time distractions increase reaction time while driving because you aren’t as alert to possible situations on the road

6. Physics Talk some distractions are difficult to avoid: sneezing bad weather sudden changes on your windshield – such as huge water from a passing truck what are some distractions that can be avoided? does everyone have the same reaction time (even while alert)?

7. Physics Talk Factors that Can Affect Reaction Time: age practice fatigue exercise overall health heredity (genetics)