Question

match the graph that best fits the motion from the data table.

time (sec)	distance (m)
5	120
10	140
15	160
20	180

Explanation:

Step1: Calculate the speed

The speed $v=\frac{\Delta d}{\Delta t}$. For the time - interval from $t = 0$ s to $t = 5$ s, $\Delta d=120 - 100=20$ m and $\Delta t = 5$ s, so $v=\frac{20}{5}=4$ m/s. For other intervals, we also get a constant speed of 4 m/s (e.g., from $t = 5$ s to $t = 10$ s, $\Delta d=140 - 120 = 20$ m, $\Delta t=5$ s). A constant - speed motion is represented by a straight - line graph in a distance - time plot.

Step2: Analyze the initial condition

At $t = 0$ s, the distance $d = 100$ m, so the graph should start at the point $(0,100)$ on the distance - time graph.

Answer:

The graph that is a straight line with a positive slope and intersects the distance - axis at 100 (the top - left graph) best fits the motion from the data table.