Name: ______Section:______Date:_____/_____/_____
Calculating Slope
Kelly took the data in the table below during lab.
Time (s) / Position (m)0 / 0
1 / 2.5
2 / 4.6
3 / 5.2
4 / 8.3
5 / 9.0
6 / 11.0
7 / 14.5
8 / 15.5
9 / 18.0
10 / 20.2
1. Make a graph of this data on the grid to the right. Mark each data point with a dot (·).
A. Put time on the x-axis.
B. Put position on the y-axis.
C. Add a title to your graph.
2. Do the data points appear to form a straight line?
A. Use a ruler or other straight-edge to draw a “best-fit” line through the data points.
B. The best-fit line should lie as close to the data points as possible; there should be some points above the line and some points below the line. Some data points may fall on the line, or you may not have any data points on your line.
3. Choose two points on your line that you could easily read the coordinates of (these do not have to be data points; in fact, they are usually not data points)
A. Mark each of these points and place a circle around each.
B. Label the first point “1” and the second point “2.”
C. Write the coordinates of each point below (include UNITS!!!):
Point 1: t1 = ______x1 = ______
Point 2: t2 = ______x2 = ______
D. Calculate the slope of your line. Use your calculator; do not leave it as a fraction.
E. Remember: the numbers you used to calculate slope have units, so your calculated slope should have units! What are the units of your slope? What variable also uses these units?
F. What do the units of slope tell you about the meaning of the slope of a position versus time graph? Notice that the equation for the slope of a position versus time graph looks very similar to the equation for the definition of that variable.
G. Using your graph, determine the position of the object at 5.5 seconds. Describe how you found the value.
H. The data for this activity was data for a moving object. How would you describe the motion of the object? What kind of object could have been used for this data?