Experts,
In prob. 508, p.126, NCEES water PM, there is solution on page 207 and I got the following errata from web.
p. 207, Water Resources and Environmental Solution 508:
The following information clarifies the existing solution.
Rainfall 1 is from time = 0 hr to time = 1 hr at an intensity of 1.5 in./hr.
Rainfall 2 is from time = 1 hr to time = 2 hr at an intensity of 0.7 in./hr.
The discharge in the watershed during the second hour will consist of:
The second hour of Rainfall 1 (1.2 cfs/in. × 1.5 in./hr × 1 hr) plus the first hour of Rainfall 2
(0.5 cfs/in. × 0.7 in./hr × 1 hr), or 2.15 cfs.
I really dont get why they calculated rainfall like this:
I belive it should be like:
The second hour of Rainfall 1 (1.2 cfs/in. × 0.7 in./hr × 1 hr) plus the first hour of Rainfall 2
(0.5 cfs/in. × 1.2 in./hr × 1 hr), or 1.44 cfs.
Also for water prob 502, solution on p.202,
third line is:
hall= 285-80.4-(120+20x2.31)
why do they use factor 2.31. I belive it should be 0.43 to convert psi to feet.
Am I right?
Can you guys please give your valuable inputs!!!!
Thanks.
In prob. 508, p.126, NCEES water PM, there is solution on page 207 and I got the following errata from web.
p. 207, Water Resources and Environmental Solution 508:
The following information clarifies the existing solution.
Rainfall 1 is from time = 0 hr to time = 1 hr at an intensity of 1.5 in./hr.
Rainfall 2 is from time = 1 hr to time = 2 hr at an intensity of 0.7 in./hr.
The discharge in the watershed during the second hour will consist of:
The second hour of Rainfall 1 (1.2 cfs/in. × 1.5 in./hr × 1 hr) plus the first hour of Rainfall 2
(0.5 cfs/in. × 0.7 in./hr × 1 hr), or 2.15 cfs.
I really dont get why they calculated rainfall like this:
I belive it should be like:
The second hour of Rainfall 1 (1.2 cfs/in. × 0.7 in./hr × 1 hr) plus the first hour of Rainfall 2
(0.5 cfs/in. × 1.2 in./hr × 1 hr), or 1.44 cfs.
Also for water prob 502, solution on p.202,
third line is:
hall= 285-80.4-(120+20x2.31)
why do they use factor 2.31. I belive it should be 0.43 to convert psi to feet.
Am I right?
Can you guys please give your valuable inputs!!!!
Thanks.
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