riment- Stralght Line Motion At Constant Speed Kakang Purpose: In Uhis experiment, the position of a bulldozer moving in a straight line is measured at various times, to determine the bulldozer's speed, Procedure: 1. Allow a toy bulldozer ton travel across a table top or the floor for a distance of 3 or 4 meter in a test run. 2. Place a tape measure or a series of meter sticks along the path of travel. Start the bulldozer a few centimeters before the starting line. When the bulldozer reaches the starting line, start keeping track of the time with a stop watch or sweep second hand. 3. Five seconds after the bulldozer crosses the starting line, record its position. Without stopping the bulldozer, repeat this procedure at 5-second intervals. Enter all of the data in the first column of the data chart. 4. Reduce the speed of the bulldozers by forcing it to drag a load behind as it traveís. Following the procedure above, record the position of the bulldozer at the end of each 5 seccond interval in the second column of the data chart. 5. Add heavier weights behind the bulldozer to reduce its speed further and record position and time in the remaining columns of the data chart. Data Chart: Trials Experiment #1 1 Position of bulldozer in cm. (x) Trials Experiment #2 3 Time in seconds (t) 2 3 average 2 average O cm Ocm ocm o cm o cm ocm 5 87cm 91 cm 95 cm 91 cm 70 cm 68 cm19 Cm12 Cm 10 160em/65 cmm176 cm167 Cm 135 cm138 cm 147 cm140 cm 15 242cm 2470254 cm 248 Cm 191 cm/201 cm/204 cm201 Cm 20 329cm 325 Cm325 cm 326 cm 251cm/253 cm/266cm251 Cm 25 404 cm 39ccm403cm 401 cm 316 cm310 cm323.c316 Cm 38703720m 3820m 380 cm. 30 Average speed (Vav) in cm /sec 186 204 Cm/S 225 cmS224 cms 238 227 cml 244 181 Data and Analysis: 1. For each trial, calculate the average speed, Vav, by dividing the total change in position by the total time interval that elapsed, t. 2. Use the data for the first trial to plot a graph of position vs time. 3. On the same piece of graph paper, plot a graph of position vs time for each of the other trials you ran. label each graph with the number of the associated trial.- 4. The shape of a position vs time graph for motion at constant speed is a straight line. Do your graphs have this shape? -10-