Question 732727
A long straight river, 100 meters wide, is flowing at 1 meter per sec. A pollutant is entering the river at a consistent rate from one of its banks. As the pollutant disperses in the water, it forms a plume that is modeled by the equation y= the sqare root of x.
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How wide is the plume at 25 meters?
y = sqrt(25) = 5 meters.
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How wide is it at 100 meters?
y = sqrt(100) = 10 meters
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How far down from the river source does the pollutant plume reach halfway across the river?
Solve: 50 = sqrt(x)
x = 2500 meters
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How far down the river does the plume reach the other side?
Solve: 100 = sqrt(x)
x = 10,000 meters
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Cheers,
Stan H.
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