How friction and gravitational potential energy affect the distance travelled by a toy car from an incline plane of different heights and textures.

Apparatus

• Toy car.
• 5 x 1 metre rulers.
• Incline plane with 5 different height settings (5cm, 10cm, 15cm, 20cm and 25cm).
• 4 different surfaces for the ramp (wood, carpet, rubber and sandpaper).

Diagram

 

Method

• We are going to set up the apparatus as shown in the diagram with the metre rulers starting at the bottom of the ramp.
• We decided to use 5 metre rulers after we did some preliminary tests to see how far the toy car would travel on the highest height with the smoothest surface.
•  For each height and surface we are going to test the toy car 5 times, we will take the average (mean) score as our result to make it a fair test.
• We will have one person letting go of the toy car from the top of the ramp and one person recording the distances achieved.
• We are going to measure the distance travelled from the front of the car at right angles to the metre rulers.

Variables

• The height of the ramp.
• The texture of the ramp.

Results Table

MGH = Mass x Gravity x Height

Conclusion

I found from my experiment that Sandpaper, Wood and Rubber were all quite equally matched I think that this is because they all have very similar amounts of friction with the toy car’s wheels.  Carpet got quite significantly lower results than Sandpaper, Wood and Rubber I believe that this is because there was much more friction acting upon the wheels of the toy car on Carpet than on the other three surfaces.  The distance travelled using Carpet at a height of 5cm was 0cm.  This was because there was more friction than gravitational energy so the toy car did not move (see highlighted areas on results table).

You can see from the graphs that as the height of the ramp (gravitational potential energy) got greater the distance travelled by the car on all four surfaces got greater also.  This is because the gravitational potential energy outweighs the frictional energy making the car travel further.

The results from my experiment however did not match my prediction as the toy car travelled the furthest distance on the Sandpaper surface set at the highest height (25cm).  I predicted that the toy car would travel the furthest on the highest height with the surface with the least friction.  I do not believe that Sandpaper has the least amount of friction out of the four surfaces tested.  I think that the surface with the least friction is Wood.  I think that I got this result because it was anomalous (as shown on the graph for wood).

Evaluation

I think that my experiment and method were quite accurate this is because out of the 20 average results only 1 was anomalous (25cm on wood). I could improve my method by talking more results this would decrease the chance of getting an anomalous result.

I could take this experiment further by having the same surfaces on the floor, as on the ramp, this would show how friction slows down the toy car.  If I did this experiment I would use the same car and start heights to compare my results with those on a concrete floor as in my first experiment.  I would expect that Carpet would get the least distance and Wood would get the furthest distance, I would take more results so that there is less chance of getting an anomalous result.