Part II - REACTION TIME

1. Measure your reaction time by trying the following: smooth out a dollar bill and have a friend hold it vertically as shown. Put your thumb and index finger on either side of the bill without touching it, about halfway down for the first trial. When your friend releases the bill try to catch it. (Do you see the makings of a good bet here?) On subsequent trials, find out how far down the bill you have to place your fingers in order to catch it, and estimate the uncertainty in this. Use to calculate an estimate of your reaction time, and calculate the uncertainty in this estimate.
2. Now measure your reaction time by using a digital electronic timer in ``sensed start/stop" mode. In this mode, the timer starts when one light beam is interrupted and stops when the other light beam is interrupted. See how soon after someone starts the timer that you can stop it. Repeat the measurement a few times. Is the result of these measurements consistent with the estimate of your reaction time and its uncertainty made using the dollar bill?