Information about water (A chart from Ministry of Environment of Korea) http://edu.me.go.kr/env2/index.html The volume of water - 1ml = 1cm^3
Information about rice • An adult eats approximately 220g of rice a day. • The volume of cooked rice is twice bigger than raw rice. • Volume of rice- 1g = 1cm^3
Water container in real life http://www.ipco.com.sg/watter.htm http://www.piedmontsub.com/Gville.shtml Usually cylindrical shape
Food container in real life http://www.foodmixers.com/models_vessels.asp
How much water are we using per day? • A shower- 30L • A bath- 80L • Washing Machine- 100L • Washing Dishes-20L • Drinking Water- about 2.6L • Flushing Toilet- 10L
The amount of water we are going to supply A person uses about 212L of water a day. A family of 2 adults and 2 children will use 212L*3(2 children use 212L)=636L 636L-100L(washing machine)-240L(Bath)-40L(2 times of washing dishes)= 260L 50 families will use 260L*50=13000L a day. ∴13000L*14=182000L for two weeks.
Water Container • Shape- Cylinder (Not fragile) • A cylinder’s TSA calculation method = πr^2 + 2πrh = πr(r+2h)
Justification • Sensible height -Using 2m as the radius of the container gives us the cheapest cost. However, if we use 2m as the radius of the water container, the height is too high. (14.5m is about the height of the fifth floor of an apartment.) Thus we chose stability rather than cheap cost, and decided to use 3m as the radius.
Justification • For the concrete floor, we added 1m margin for every side to make people easy to step on it. • Costs are rounded up to the nearest whole number- To show the clear differences between values
Final Decision • Height- 6.5m • Radius-3m • Volume- about 182m^3 • Cost of cylinder- $2507 • Cost of cement floor-$3200 • Total cost- $5707
How much food do we have to supply? • An adult- eats about 0.25kg of rice a day • A child- Assume that a child will eat the half of the amount an adult eats a day • A family(2 adults, 2 kids)- Eats about 0.8kg of rice a day • 50 families for 2 weeks- 0.8kg*50*14 = 560kg
Food container Shape= Rectangular prism 1cm^3= 1ml= 1g ∴ 1kg= 1000cm^3 ∴ 560kg= 560000cm^3 (= 0.56m^3)
Justification • Sensible shape -We chose rectangular prism for the shape of the container, because the pack of rice is shaped like a rectangle (with smoother edges). Since rectangular shape is easy to contain rectangular objects, the pack of rice will fit easily in the rectangular shaped container.
Justification • Rounded up to the nearest whole number- Shows a clear change between two values. • No floor- Water container needs a steel floor to contain water (liquid), but steel floor is not needed to contain rice (solid). • For concrete floor, we only added 0.5m margin each for every side, since the size of the container is very small.
Final decision • Length, height= 1m • Width= 0.56m • No floor • Volume= 0.56m^3 • Cost of the prism ≒ $52 • Cost of the concrete floor ≒ $399 • Total cost≒ $451
Bibliography http://edu.me.go.kr/env2/index.html http://www.ipco.com.sg/watter.htm http://www.piedmontsub.com/Gville.shtml http://www.foodmixers.com/models_vessels.asp