Passage
Students studied how far a toy car rolls across a flat floor after coasting down a ramp. In each trial they released the car from the same starting point on the ramp, let it roll onto the floor, and measured the distance it traveled on the floor in centimeters (cm).
Experiment 1: Using the same car and the same smooth tile floor, the students set the ramp to different angles and measured the distance the car rolled (Table 1).
| Ramp angle (°) | Distance rolled (cm) |
|---|
| 10 | 40 |
| 20 | 72 |
| 30 | 95 |
| 40 | 108 |
| 50 | 112 |
Experiment 2: Holding the ramp angle at 30° and using the same car, the students changed the floor surface and measured the distance the car rolled (Table 2).
| Floor surface | Distance rolled (cm) |
|---|
| Smooth tile | 95 |
| Short carpet | 52 |
| Rough mat | 30 |
| Sand | 11 |
Experiment 3: Holding the ramp angle at 30° and using the smooth tile floor, the students added weights to change the car's mass and measured the distance it rolled (Table 3).
| Car mass (g) | Distance rolled (cm) |
|---|
| 100 | 95 |
| 150 | 93 |
| 200 | 96 |
| 250 | 94 |
In every trial the car was released without being pushed, from the same point on the ramp.
