Question

Odina walked down the hall at school from the cafeteria to the band room, a distance of 100.0m. A class of physics students recorded and graphed her position every 2.0s, noting that she moved 2.6m every 2.0s.

Which of the following graphs represents Odina’s motion?

Answer 1

The correct graph is C. Odina moved 2.6 meters for every 2 seconds and her speed is equal to the distance she travelled divided by the time, which is $\frac{2.6 m}{2 s}$ = 1.3 m/s. The speed of 1.3 m/s is also the slope of the graph that represents her motion. From the line sketched in graph C, at 2 seconds, her distance is approximately 2.6m.

Answer 2

The right answer is c.

First, you must notice that the x-axis represents the Time (measured in second) Odina walked down the hall and the y-axis represents the Distance (measured in meters) she traveled. At this graph you can notice that just in 2 seconds the distance she traveled is 2.6 meters as indicated in the statement above. As the graph is a line, this number will be a constant, that is, she will move 2.6m every 2.0s, so:

$\frac{2.6m}{2s}=1.3m/s$

This number represents the velocity of Odina. Therefore, she moves at a rate of 1.3 meters per second