Meghan's science experiment (1st term)

How surface texture affects friction

Question:

How does surface texture affect the amount of force needed to move an object? I will test three floor surfaces: carpet, parquet flooring, and concrete.

Hypothesis:

I think that concrete will need the most force, parquet flooring will need the least, and carpet somewhere in between.

Materials:

1. a box with a hole in it
2. an elastic band
3. a small weight of about 200 grams
4. scissors
5. a rug
6. a concrete surface
7. parquet flooring

Procedure:

1. put the weight in the box
2. weigh the box with the weight in it
3. cut the elastic band so that it is now an elastic “string”
4. tie the elastic “string” to the hole in the box
5. hold the elastic band straight so that it is going as far as possible, without stretching, and measure it
6. (on the parquet flooring) hold onto the rubber band and drag the box
7. stop the rubber band and box, taking care not to stretch the rubber band any more
8. measure the length of the rubber band
9. repeat steps 6,7, and 8 on a concrete surface and on a carpet (I did it three times on each surface)

Data and observations:

The elastic band is 6.0 cm when it is straight and not stretching.

The rubber band was 7.4, 7.1, and 7.2 cm long when I dragged the box along the concrete. It was 6.5, 6.3, and 6.3 cm long when I dragged it across the parquet flooring. Last, it was 7.0, 7.2, and 7.2 cm long when I dragged it across the carpet.

Analysis:

My hypothesis was mostly right. I thought the concrete would need the most force, but it turns out that concrete and carpet are about the same.

           Concrete   Parquet   Carpet
1st time    7.4 cm    6.5 cm    7.0 cm
2nd time    7.1 cm    6.3 cm    7.2 cm
3rd time    7.2 cm    6.3 cm    7.2 cm

Conclusion:

My conclusion is that it takes the more force to push or pull something on carpet or concrete than it does to push or pull something on parquet flooring.

Reflections:

I think the carpet and the concrete needed the same amount of force because they are both bumpy.

I think the parquet flooring needed the least amount of force because it is a smooth surface and has very little bumps.

I could also do other experiments. I could use different surface textures (wood, towels, or plastic). I could measure the amount of force used to push an object. I could use a spring scale to measure the amount of force needed to lift an object.