A student investigates the friction between a plastic container and different types of floor surface.
The student places several metal weights inside the plastic container and pulls it across each surface using a newtonmeter.
Suggest why the student places metal weights inside the container.
Explain why the student must keep the total mass of the container and weights constant throughout the investigation.
The table below shows the results of the student's investigation for five different floor surfaces:
| Type of floor surface | 1st reading (N) | 2nd reading (N) | Average (N) |
|---|---|---|---|
| Vinyl | 1.8 | 1.8 | 1.8 |
| Carpet | 5.2 | 4.8 | |
| Polished wood | 2.4 | 2.6 | 2.5 |
| Ceramic tile | 3.1 | 3.3 | 3.2 |
| Rubber mat | 6.4 | 6.4 | 6.4 |
State which variable in this investigation is non-continuous (categoric).
Calculate the missing average force for the carpet surface.
State the type of graph that should be used to display these results and explain your choice.
When comparing results with another student, she finds they recorded different friction forces for the same types of surfaces. Suggest two reasons for this.
The student repeats the experiment using a wider plastic container that has the same mass but a larger bottom surface area. Explain how this change affects the pressure exerted on the floor.
Suggest two ways in which the student could reduce the friction force between the container and the floor surfaces during this experiment.
