2.11.

a. Examine the two hydro-

graphs presented below in

Figure P2-11 Ofor an

area of 5000 acres. Which

of the two is a unit hydro-

graph? Please show how

you arrived at this

conclusion.

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1200

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800

600

400

200

0

Hydrograph 1

6

Time (hr)

-Hydrograph 2

8

10

12/nLong description

Back

Q (cfs)

1400

1200

1000

800

600

400

200

b. Using the hydrograph that

you chose from part (a), as-

suming it is a 1-hr UH, cre-

ate a 3-hr UH.

0

- Hydrograph 1

6

Time (hr)

-Hydrograph 2

8

10

12

Hydrograph 1 rises from (1, 0), to a maxi-

mum at (5, 600), before falling to y = 0 at

(10, 0). Hydrograph 2 rises from (1, 0), to

a maximum at (6, 1300) before falling to

y = 0 at (10, 0).