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Appearance of parachute 1. nylon thread X8 2. white plastic bag X1 3. Straw X12 Decoration 1. newspaper 3. magazine 2. cellophane.

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Presentation on theme: "Appearance of parachute 1. nylon thread X8 2. white plastic bag X1 3. Straw X12 Decoration 1. newspaper 3. magazine 2. cellophane."— Presentation transcript:

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3 Appearance of parachute 1. nylon thread X8 2. white plastic bag X1 3. Straw X12 Decoration 1. newspaper 3. magazine 2. cellophane

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5 >>The material used does not need to be purchased. >>The material, such as plastic tablecloth, sponge…etc, may be reused again. . We use lighter material to decorate the parachute. >> Cellophane, magazine picture (x1), >>To reduce the mass of the whole parachute. To increase the air resistance so as >>>to protect the egg

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7 1.Terminal velocity (1) At the very beginning, F 0 ∴ the parachute accelerates ( velocity v ↑) (2) v↑ F ↑ (3)Finally, W = F  net force = 0 ∴ the parachute move with constant speed( terminal velocity)

8 2. Time of impact The bottom of the parachute is stuck with a piece of sponge. When the parachute reaches the round, the compression of the sponge increases. This can reduce the impact force acting on the parachute Thus the parachute and egg won’t be damaged so easily.

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10 We tried twice to have the parachute fallen from the 4/F to the ground. Firstly, it was not successful. Secondly, it took about 12 seconds to reach the ground and the egg didn’t break after falling from the 4/F.

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12 We learn a lot from this assignment. Not only can we learn the principle of Physics(Force and Motion), we can also learn the importance of cooperation in team work. We have a lot of fun on that and hope that the same type of assignment can be organized next time for us to apply our skills and knowledge.

13 .how air resistance affects the motion of the parachute.the fluid friction can oppose the motion.increase the size of the parachute can greatly increase the air resistance and when air resistance is the same as the weight of the object, the terminal speed of it can be reached. Reducing terminal speed make it safe enough for the egg to land onto the ground. Learning(Force and Motion)

14 Learning(cooperation).We need to have a close cooperation between each member so each person can do her own job properly.. We can do the job properly,our friendship can be strengthened during our meeting.

15 Although we can apply the knowledge of Physics to protect the egg, we have thought about some improvement for this assignment so that we can improve our skills on it.

16 Method 1 Make the size of the parachute bigger. Reason: to increase air resistance and reduce the terminal speed. Method 2 Reduce the mass of the object which contains the egg Reason:the difference between the weight and air resistance is smaller and rate of increase of speed (acceleration) will be smaller.

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18 Ko Wing Ki 4E (4) When I know that Physics assignment is to make a parachute to protect an egg,I am interested in it. Although we have learned much knowledge on each subject, those are the basic for us to know about or learn, we have no chance to apply the knowledge and the theory such as the Newton’s first law of motion to our daily life except the experiments during the lesson. It is more important for us to apply the knowledge.

19 Since each person in my group cooperate properly, we finished it in a few days only. I think that the most difficult things are the design of the container which contains the egg and how to apply the knowledge of the laws of force and motion so we need to search the Internet for a long time. Unfortunately, I cannot find something useful. Finally, I use my own idea on the design. I try to use some reusable materials such as newspaper and magazine paper to cover the container so it can reduce the weight of the object and not too much money is spent on the project. According to the Newton law of motion, since the surface area is increased when the parachute opens, the air resistance is greatly increased and so the terminal speed can also be reduced.

20 Luckily, the time of the parachute to reach the ground is the greatest. I felt very surprised. I have learned many things in the assignment - the principle applied and the importance of cooperation. Based on my knowledge of Economics, the division of the labour will increase the productivity of the production since each person concentrates on different job. Also, I can review on my past experience when I was in primary school. I have done the same assignment, ‘how to use the parachute to protect the egg’ and I know that one of the important thing is to use suitable numbers of rope. I hope that I can have another chance to do the same type of assignment and improve my skills.

21 Kong Ki Chi 4E (5) This is the first time we made a parachute. We tried our best to do this project, although we didn’t know if it is success or not. We tried to cut a hexagon, circle and square and we thought square parachute was the best. We tried a small one but it was falling too fast and was not stable. Then we tried a bigger one, it was better than the small one. Also, we used a long rope instead of a short one. The egg didn’t break after falling from the 4/F.I think the parachute design is more important than the protection of the egg.

22 After this activity, I know that cooperation is very important. We need to have a close cooperation between each person so each person can do their own job properly. We have done a lot of experiments and have discussion after each trial. At last, our parachute spends the longest time to land compared with other groups in our class. I am very proud of my group and myself. Lam Nga Ching 4E(8)

23 Making our parachute, we consider how air resistance affects the motion of the parachute and how to reduce the impact force acting on the parachute on landing.This help us to revise the Newton’s Law of motion.We also search information of parachute through the Internet. We learn much extra knowledge about parachute. I also find physics very important in our daily life. Physics can help improve our living standard.

24 When my classmates tested their own parachutes, the ambiance was very exciting. I was completely immersed in this activity. I was also very excited. When our teacher announced which group had the longest time of fall, all of my classmates were very nervous. Members of my group were very happy as our parachute spent the longest time to fall. I also found many beautiful and creative parachutes being made by my classmates. I think this activity is meaningful and exciting.

25 Lam Yuen Man 4E(9) I think this activity is very meaningful. To make a parachute, we have to revise the related topics such as terminal speed. Also, we have to find information on nternet or books. Although it is quite hard to find useful information from the bulk of things on the internet, it is a chance for me to be active in learning. Doing research on the parachute, I understand more on parachute and the physics principles behind. Therefore, the activity allows us to do revision on the things that we have learnt and leads us to be active in learning.

26 Besides, making a parachute allows us to apply physics in our daily life. This not only let us have a better understanding of the topics that we have learnt, but also motivates me to learn. After doing this project, I understand that physics are everywhere so I should try to be more curious to find out physics in daily life.

27 In addition, when we made the parachute, our group members were working together. We have failed at the first time, but after having discussion on improving the parachute and several trials to test the function of the parachute, we succeeded. That gives me a great feeling that it is worth paying effort to make the parachute and also gives me a sense of satisfaction of team work. Also, when we dropped the parachute from the 4 th floor in the New Wing of school building, our class found it very exciting. Most of our classmates enjoyed the lesson very much. All in all, this activity is an interesting way for studying. Therefore, I hope we can have more similar activities.

28 Leung Mei Ling 4E(10) With this experiment, I feel really excited. Our group got the best result in the class. It makes me feel being successful. And, I know more about the principle of parachute. We need to concern the velocity of it, the force acting on it and how to protect the egg well by other material. I found that reducing the landing velocity is really important for protecting the egg.

29 In my group, all the members are very nice and responsible in doing this project. We discussed together and had some different ideas, and then we tried them all. Finally, we accepted the best one. The feelings are so funny and happy. I am so glad to finish the project. I think doing a project is good for me to study!>w<

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