Thematic inquiry My perfect parachute 專題探究 我的完美降落傘

Table of contents Definition of perfect parachute First experiment (Including objective, variables, process, results and conclusion) Second experiments (Including objective, variables, process, results and conclusion) Overall conclusion Reflection

Definition of "perfect parachute” The perfect parachute in our standards should: Descend slowly in order to protect the weight/cargo (e.g. A person or package) Actually glide down instead of full on dropping which would mean damaging the weight/cargo.

First Experiment

Objective Which shape, round or square, makes the parachute descend quicker? 測試圓形和正方形哪個形狀能令降落傘的下降速度更慢 or

Variables 設計公平實驗 Shape of the parachute Weight of parachute variable to be changed variable to kept constant Shape of the parachute Weight of parachute Number of ropes Material of parachute Length of rope Variables to be changed A constant variable Parachute area 降落傘的面積 The shape of a parachute (square and round) Length of a rope 繩子的長度 Parachute material 降落傘的材料 The number of parachutes 降落傘的層數 降落伞的形状 (正方形和圆形) The number of ropes 繩子的數量 Comparison: which is slower the circular or square parachute? 比較：圓形和正方形的降落傘哪個下降速度較慢

Process 1.Two parachutes of the same area are made of plastic bags, thread and adhesive tape. They are round and square. 1.相同面積的兩個降落傘由塑膠袋，線和膠帶制成，分別為圓形和正方形的。 2.Put two parachutes down at the same height.(*It must be the same person) 2.在同一高度放下兩個降落傘（*必須是同一個人放下降落傘） 3.Record the fall of two parachutes(*Those who record time must be the same person who starts shouting) 3.記下兩個降落傘的墜落時間（*記錄時間的人必須是開始喊叫的同一個人） 4.Calculate the average of descent speeds and compare the landing speeds of round and square parachutes 4.計算下降速度的平均數，對圓形和正方形降落傘的降落速度作出比較 5.Discuss the difficulties encountered and solutions 5.討論遇到的困難和解決方案 6.Draw conclusions and prepare for the next experiment 得出結論並為下一次實驗做準備

C. Results 記錄 Round Square 7.5s 8.2s 6.9s 10.00s 7.6s 7.3s After a lot of many experiments, we came up with this → 經過許多實驗後，我們得出了結果 → There is the average time 這個是平均時間 ↓ Round Square 7.5s 8.2s 6.9s 10.00s 7.6s 7.3s win! Round Square 7.23s 8.21s

D. Problems 讨论 1.Rope length 2.Falling position There may be an error in the length of the rope 绳子的长度可能有误差 In the position and height change, there may be a relatively larger error 位置，高度变化，可能会有比较大的误差 Solution:When you cut the rope, fold it in half and then cut. 改进：当你切断绳子时，将其折叠起来 Solution: People who drop it shouldn’t move and put their hands on top of the wall 提高：放降落伞的人不要动，把手放在墙上

E. Conclusion 結論 We came to the conclusion that squares fall slower than the circular parachute. But after thinking about it, we thought that there was a lot of room for reformation in the circle, so we decided to modify it on the circular parachute and change the original four ropes into eight. 我们得出了结论，正方形比圆形降落伞下降速度更慢。但思考过后我们觉得圆形有很大的改造空间，所以决定在圆形降落伞上进行修改，把原先的四根绳子变成八根

Second Experiment

Using 4 and 8 rope separately, which parachute would descend quicker? Objective Using 4 and 8 rope separately, which parachute would descend quicker?

Variables Variable to be changed Variable to be kept constant The number of ropes The material of the parachute The weight of the parachute The total surface of the parachute The shape of the parachute

Process Add 4 more strings to the square parachute from the last experiment and make another square parachute. Two members will record the parachute dropping and record the time it took. One of the two students will give a signal and another member will drop the parachute. Record the time and video. Calculate the average descent speeds of both parachutes. Discuss the results, possible problems and solutions. Draw conclusions

Results 7.5s 8.0s 6.9s 7.8s 7.6s 8.3s 7.4s Four ropes Eight ropes After 4 tries, this is our results. The average time of the four ropes is 7.23s. The average time of the eight ropes is 7.88s.

Conclusion Our results conclude that the parachute with eight ropes descends slower than the one with four ropes. However, the difference is only slightly off by 0.65ms. In the case of our experiment, the parachute with four ropes won.

Overall Conclusion

Results from both experiments In the first experiment, we concluded that the square parachute won. We used the same parachute in the second experiment in addition with another square parachute made the same way. In the second experiment, we concluded that the parachute with four ropes descended quicker and thus came an overall conclusion. Overall, with a combination of both the square parachute and the four ropes, we created the perfect parachute by our standards.

Reflection

Thank you for listening.