Science Camp (Physics) Part 3 : Project (Paper chair) Presented by : Li Man-long and Lai Chung-sum

Reasons for choosing this topic Paper chair is a challenging option to choose. Although paper is soft material, we still can use it for holding some heavy objects. There are many physical theories contain inside. After the discussion between us and other group, we want to have the same topic, hence can compete with other.

Planning / design Material: wasted card boxes, scissors, cutters, sticky tapes. Location: school and campsite Budget: 2 rows of sticky tapes----$10 Procedure: 1. Cut down the card boxes into pieces by cutters and scissors. 2. Sticky tape is used for sticking papers into different shapes or different part of the chair.

Data collection and analysis Sample one First model Base of first model: 5 paper cylinders

Data collection and analysis Sample one Result of sitting a man on chair is that the chair is collapsed Second stage of model: 4 paper triangle

Data collection and analysis Sample one Failure : The base of the model is collapsed. There is no enough support on the center part of chair and the length of 5 cylinders are not same Improvement :Add one more cylinder at the base, and make all cylinders have equal length. Result: The chair is still collapsed.

Improvement Use a harder card to replace paper. Not build too high for the chair which can make the chair not easily to collapsed. Make sure there is no any clipped line on the paper.

Conclusion 5 circle-shaped cylinders can only give out a few support as they placed away from each other. Furthermore, every cylinders cannot share equal fore acting on it. So it is not a suitable option. 4 triangle-shaped cylinders can give out lots of support. It is because they cover more surface area when the force acting on it. so they can hold on more pressure,according to the pressure law (Pressure = force / area) Shorter stand can burden more pressure.