Examine the graph of position vs time over the time intervals you just identified for increasing and decreasing velocity. The rate of change of velocity is called acceleration . If velocity is in miles per minute, then acceleration is in miles per minute per minute. Make a scatter plot of the acceleration estimates to obtain an approximation to the runner's acceleration curve. Use the acceleration curve to obtain new estimates for those time intervals in which the runner's velocity is increasing and those time intervals when it is decreasing.
Positive acceleration corresponds to increasing velocity.
Negative acceleration corresponds to decreasing velocity. Compare these estimates to the estimates obtained directly from the velocity curve above. Formulate a statement describing the relationship between positive acceleration and the shape of the graph of position versus time. Include a statement describing the shape of the position versus time graph when the acceleration is negative. Copyright 1995 by PWS Publishing Company, a division of International Thomson Publishing Inc.