These are some key factors that I must consider: I might not drop them from the same height every lesson but I will use an area in my school which has an open banister of 4.00m in height, this will be used as my dropping point which will allow me to keep the experiment fair and allow all the helicopters to be dropped at the same height. The door might be open at the foot of the stairs this may cause a slight breeze to blow through and therefore blow the helicopters off course. To not allow this I will ensure that this door is closed at all times during the testing times.
An experiment to investigate how the wingspan changes the speed in which a paper helicopter falls.
My Hypothesis:
I predict that the greater the wingspan the slower the time it takes to land. I think this because the longer the wingspan the more air resistance the helicopter will therefore have. Here is a diagram which shows the air resistance on the wings.
The direction of the black arrows shows why the helicopter spins. The force is forced to one side pushing the wing out of the way. This will cause the force to be greater if there is a bigger surface area causing the helicopter to spin more slowing the aircraft down.
Preliminary experiment
I have decided to complete some preliminary results because I think they will be useful in checking that the experiment is successful and to see whether any changes need to be made before the final experiment takes place. Here are my results:
From this data I have come to the conclusion that to do this experiment I will need to record the data from the time the spinning motion begins. I have also decided to increase the accuracy of my results by adding more variations of the helicopters. I will also use one helicopter and cut the wings as each length decreases, this will ensure that the helicopter is always exactly the same size, weight and dimensions as before, except for the obvious variation, the wingspan.
Apparatus used
- Stopwatch
- Tape measure
- Ruler
- Scissors
Materials used
Diagram of the experiment
The Method
- Make one paper helicopter and place the paperclip on the end. This helicopter should have a wingspan of 16cm.
- Drop the helicopter from the measured and desired distance and time from the beginning of the spinning motion. Stop the stopwatch when the helicopter hits the ground.
- Repeat eight times.
- Now cut one centimetre off the wingspan and repeat this method.
- Stop when you have done the eight drops of the helicopter with a wingspan of six centimetres.
Make sure that safety is aware, do this by being safe at the drop point and always being sensible.
My Results:
The graph on the next page includes all the data except for the averages, this shows a wide range of data. I have included the anomalies for added effect to show how random the data was.
The graph below is one that is of the averages to give me an overview of the data, I will then go on to analyse the graph and use my scientific knowledge to explain it.
According to the results I have found that there is a faint relationship between the wingspan of a paper helicopter and the time it takes to fall. The experiment wasn’t a very successful one because there were many anomalous results. As you can see the graph doesn’t show a definite pattern. It is evident that the most reliable and successful wingspan is 11 cm as it was that measurement which took the longest to fall. The helicopters with the wingspan of 15cm and 16 cm seem to have the shortest falling time, this is because they were over balanced the force on the wings, which occurs from the weight of them, causes them to expand in the wrong direction and fall with barely any spinning at all. This would explain the gradual decline after the peak, ending with the steeper decline at the end. The results don’t support my hypothesis for these reasons.
Evaluation
I feel that my method wasn’t a very successful one because of the place in which we decided to base the experiment. The actual timing etc was successful though. The anomalous results are because they kept hitting the banister to the stairs; this could have caused the results to differ. To improve my results I would have not included these timings in my results and would have dropped the helicopters in a different place. Another reason why the results were inconsistent could be because at some moment during the experiment a draft would be blowing, this could have blown the helicopters off course.
The overall reliability is not very good; I don’t feel it is sufficient to support my hypothesis because of all the anomalous results.
If I could do this task again I would investigate the same subject but I would improve it by setting the experiment in a quieter more open area to avoid the anomalies. Then it would be possible to create a more valid set of data and come to a more specific conclusion.
I would have also changed a different variable, height:
- Drop the helicopter at various heights recording with a stopwatch.
- Make sure that the heights are measured accurately
- Make sure that the same helicopter is used.
