- What height should we drop it at?
Since we experimented with the height of 155cm and it worked perfectly, we decided that we would round up the number to the nearest hundred (so that it could be measured easily) and use that number as the height to drop the sycamore seed from. Thus we dropped it at a height of 200cm.
- What should the wind speed be when we drop the sycamore seed?
In this situation we decide to play around with the anemometer. We discovered that no matter what you do ,the wind speed will never be the same unless it is zero. Therefore to achieve a wind speed of 0m/s we would have to shut all windows, doors, fans , air conditioners, etc.
Prediction:
The heaviest sycamore seed will have the shortest landing time.
Hypothesis:
Variables:
Independent:
Mass (g)
Dependent:
Time of sycamore seed landing (sec)
Control:
- Height of drop
- Model made out of same material
- Model of sycamore fruit has “wings” of the same length
- Wind speed
- Mass added on the same place
Fair test:
- Height of drop will be two meters
- We will make a model out of a piece of cardboard with the measurements on the cut out sheet and will only use one model.
- To prevent the wind speed from changing, the experiments will take place indoors. The windows, air conditioner and doors will be closed therefore the wind speed will be zero throughout all the experiments. To insure this fact, a anemometer (apparatus that measures wind speed) will be present.
- Every time blue- tack is added to the model to increase it’s mass it will be added on top of the previous.
Apparatus:
One anemometer (gadget to measure wind speed)
A pair of scissors
A glue stick
One piece of cardboard
A packet of blue tack
Two rulers (100cm)
Electronic measuring scale
One stopwatch
An empty room
The cut out sheet
A pencil
A 30cm ruler
Method:
- Copy the diagram on the cut out sheet on to a piece of cardboard. Use a 30cm ruler to make sure the measurements are the same as labeled on the sheet.
-
Cut along the bold lines.
- Fold along the dotted lines.
- Fold part A forward.
- Fold part B backward.
- Fold in part D .
- Fold in part C so it overlaps part D.
- Glue both parts together.
- Go to an empty room.
- Put blue tack behind two of the 100cm rulers.
- Label one of the rulers A and the other B
- Stick ruler A on the wall. Make sure it is touching the ground.
- Stick ruler B on top of ruler A.
- Weigh the model in grams using the electronic weighing scale.
- Record the mass in your results table.
- Close all windows and doors.
- Close all air conditioners and fans.
- Measure the wind speed. Make sure the wind speed is zero.
- Hold the sycamore seed in your left hand and the stop watch in your right hand.
- Make sure you are holding the model at level to the top of ruler B.
- As soon as you let go of the model start the timer.
- When the sycamore seed touches the ground stop the timer.
- Record the time in your results table.
- Repeat instructions 20-24 four more times .
- Now, add a bit of blue tack on the bottom of the model.
- Measure the weight in grams
- Record the mass in your results table.
- Repeat instructions 20-25
- Add more blue tack on top of the previous bit you added
- Measure the weight in grams .
- Record the mass in your results table.
- Repeat instructions 20-24.
- Repeat instructions 30-33 five more times.
Measurements:
I measured:
- Mass in grams,using the electronic scale. and weight in newtons (N)
- Time in seconds
- Wind in meters per a second
OBTAINING EVIDENCE (8)
ANALYSING EVIDENCE AND DRAWING CONCLUSIONS(8)
Diagram/Graph and Conclusion
EVALUATING EVIDENCE(6)
Evaluation of method
If I were to do this experiment again I would add shape as a control variable list. I would do this because as we added the blue tack the shape changed, which caused the sycamore to spin differently. I would also add, “same person doing all the experiments” as a control point
Evaluation of Results
The results were fairly accurate as the differences of results (when repeated) varied from 0.00 to 0.70. However, when I changed the mass of the sycamore seed from 5.24 grams to 7.69 grams both the average time of landing were 0.63 seconds. I think this happened because Susan recorded the time of landing for 5.24 grams and I recorded the time of landing for 7.69 grams.