Brisbane , the third largest city in Australia and the capital of Queensland, was severely flooded , natural disaster not seen here since 1974. As I write this post , thousands of volunteers help people and businesses affected to clean and back on their feet volunteer Brisbane.
The media provided extensive coverage of the disaster and its consequences for the week , providing opportunities for math teachers to study with your students some statistics cited . This article explores a particular statistic , the amount of water released from Wivenhoe Dam in a day. There are many similar opportunities for the math teacher who wants to integrate a "real math " with interesting links to relevant topical issues volunteer Brisbane.
Volunteer BrisbaneFlood 1893
There are more than 100 years, in 1893 , volunteer Brisbane has experienced severe flooding downtown and suburban low altitude when the volunteer Brisbane River burst its banks in February 1893 after tropical cyclones : The 1893 flood was only one of several floods across this time , there are other floods in 1887 volunteer Brisbane, 1890 and two in 1893 a fortnight after the great flood .
Volunteer Brisbane Flood 1974
In January 1974 , after weeks of heavy rain, cyclone " Wanda " developed on the coast of Queensland, which is then transformed into a tropical depression and dumped huge amounts of water in the city and on the side of the volunteer Brisbane River basin. The result was the flooding of the river and many low- suburbs of the city , and more than 6,700 homes were flooded volunteer Brisbane.
Wivenhoe Dam
After the water has disappeared and planners had the opportunity to analyze the cause of the flood and how they could prevent the devastating flooding of many homes and businesses were repeated, it was decided to build a large dam upstream of volunteer Brisbane, as a measure flood mitigation . This dam is Wivenhoe Dam : This dam , which is currently filled with huge amounts of water above the weir , is an impressive structure with impressive statistics :
Height : 50 meters
Length : 2.3 km
Capacity: 2640000000 cubic meters
Area: 109.4 square meters
Coastline : 462 km
Catchment area : 7,020 square kilometers
Average annual rainfall volunteer Brisbane: 904 mm
Maximum capacity: 225%
Floods, volunteer Brisbane, Queensland, Australia 2011
At the time of this article, volunteer Brisbane is slowly recovering from the serious new floods, the summit was the January 13, 2011 . Although the peak of the flood it was about 1 meter below the summit in 1974 , this time 20,000 houses were flooded , and the economic cost is much higher. In the media coverage of this natural disaster, Wivenhoe Dam has understandably attracted much attention. In particular , the management of water held behind the dam and the water released over the spillway is of great interest to the people of volunteer Brisbane . In addition to the release of water volunteer Brisbane, more than 645,000 megalitres of water were released in a day. This is about half of that part of the flood mitigation storage in Wivenhoe , which is 1,450,000 megalitres on top of stored water for consumption and supply of volunteer Brisbane.
How much water is that?
Six hundred forty-five thousand megalitres looks great - it is . But this water is very hard to see. How a teacher helps students understand this much volunteer Brisbane?
Step 1 : What is the size of a liter?
A liter is a known students who buy milk in liters quantity. Can be converted to 1000 ml , or 1000 cubic centimeters. This is the same volume of a thousand block position values , which is a cube of 10 centimeters volunteer Brisbane.
Ask students what they have the same volume as a liter - one liter of milk , of course, a bottle of soda average , less than an old brick house style volunteer Brisbane.
Step 2: Demonstrate a cubic meter
If you have a kit cubic meters, may build a cube meter lengths of one meter of timber connectors and corners . What is reality? Students may be surprised at the size when they see a real cubic meter. See how many students could fit in this space.
Ask students how many liters equal to the volume of one cubic meter. Show them thousands block comparison . Students should see that the only liter block is one tenth the size of a cubic meter in each dimension of length volunteer Brisbane, width and height. Clearly, the cubic meter volume of 1000 liters . What is another name for a thousand liters ? The prefix "mil" is " kilo " 1000 liters = 1 kiloliter . What is the mass of one cubic meter volunteer Brisbane? One liter weighs about one kilogram ( at 4 ° C is the exact mass ) . So kiloliter cubic meter or water has a mass of 1000 kg and a ton! Students may be surprised to find that a cubic meter is about the same weight of a small car.
Step 3: Analyze a family , a greater amount
Depending on where you live , students can become familiar with the pools of households. In volunteer Brisbane, many families have their own " backyard pool " . These pools are usually about 7 or 8 feet long , 3 or 4 meters wide and 1.5 m deep. This pool is a typical size of this type , and contains 50 000 liters or 50 cubic meters.
Otherwise, students can become familiar with a large swimming pool. An Olympic swimming pool of 50 meters long, 25 meters wide and 2 meters deep. Its capacity can be calculated using the formula for the volume of a rectangular prism : Volume = length x width x height = 50 mx 25 mx 2 m = 2500 cubic meters
Some communities have water tanks internal collection , which can be about 500 liters for a small tank , or several thousand liters larger .
Ask students to compare the amounts of water with other liquid volumes of knowledge. How can fill a bathtub with water in households tank volunteer Brisbane? How many trays of ice cream would fill the backyard pool ? What is the mass of water in a pool or deposit will be ? How many people are needed to lift ?
Step 4: Calculate the volume of rainfall and flood flow
Continuing in the same way volunteer Brisbane, students can calculate comparisons between domestic pets amounts of water and the amount of water in a dam or flood. For example , water released from Wivenhoe Dam in one day was 645,000 megalitres . How is it ? First, certain conversions :
645 000 645 000 000 000 milliliter = L = 645,000,000,000,000 ml
We have bigger units that can be used instead megalitres : thousand megalitres is gigaliter . thus :
645 000 ML = 645 GL
Second, the amount of space it takes? If you put water into a tank, the size would be ? Since 1 cubic meter = kL , we can work that GL 645 = 645 million cubic meters. If it was in a square tank of a mile on each side , water would be 645 feet deep - if the Empire State Building could be eliminated in the tank , which would be 200 feet of water in its upper most developed form.
How many Olympic swimming pools that fill with water? 258000 .
How many cubes 5 liters of ice cream would fill it? 1.2 billion.
Third, how heavy is the water? Since a cubic meter of water weighs a ton , 645 GL of water would have a mass of 645 million tons. This is the dough volunteer Brisbane:
6,450,000 railway trucks carrying 100 tonnes each
about 1.9 million jumbo jets full load
Finally , the amount of water supplied to the human ? Each person should drink about 2 liters of water per day. 645 GL to provide drinking water to approximately:
320000000000 town for a day volunteer Brisbane- 50 times the population of the earth.
To provide drinking water to two million people in volunteer Brisbane, this amount of water to supply its consumption needs for:
160,000 days , or 441 years .
Of course , people use drinking water for more volunteer Brisbane, if a more realistic estimate is based on the average daily water use by citizens volunteer Brisbane- 150 L each:
2150 days or 5.8 years .