A 350 m^3 retention pond that holds rainwater from a shopping mall is empty at the beginning of a rainstorm. The flow rate out of the retention pond must be restricted to 320 L/min to prevent downstream flooding from a 6-hour storm. What is the maximum flow rate (in L/min) into the pond from a 6-hr storm that will not flood it? a. 5,860 L/min b. 321 L/min c. 1.290 L/min d. 7.750 L/min

Question

Engineering

Rhys Levine

22 August, 17:19

A 350 m^3 retention pond that holds rainwater from a shopping mall is empty at the beginning of a rainstorm. The flow rate out of the retention pond must be restricted to 320 L/min to prevent downstream flooding from a 6-hour storm. What is the maximum flow rate (in L/min) into the pond from a 6-hr storm that will not flood it? a. 5,860 L/min b. 321 L/min c. 1.290 L/min d. 7.750 L/min

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Answers (1)

Know the Answer?

Lisa Kent · Answer 1

correct option is c. 1.290 L/min

Explanation:

given data

retention volume = 350 m³

flow rate out = 320 L/min

time = 6 hour

to find out

maximum flow rate (x)

solution

we apply here Mass rate of accumulation formula that is

Mass rate of accumulation = mass rate of input - mass rate of output ... 1

350 * 1000 L/m³ = x * (6hr * 60min) - (320 L * 6 hr * 60 min)

3.5 * 10³ + 4.65 * 10³ = x * 360

x = 1290 L/min

so correct option is c. 1.290 L/min