A rectangular pool, 10 m x 25 m, is to be filled to a depth of 3 m. For filling time of 2 hours, determine the inflow required in m3/sec. If 6 cm hoses are available and the water velocity in each hose is limited 2.5 m/sec, determine the number of hoses required.
Answers
Explanation:
Given : It takes 3 hours to fill the pool with the red hose. It also takes 45 minutes to fill it with the red and blue hoses at same time and 90 minutes to fill it with red and green hoses at same time.
To find : How long does it take to fill the pool with all three hoses at same time
Solution:
3 hours ( 180 mins) to fill the pool with the red hose.
=> Red hose fill in 1 min = 1/180
45 minutes to fill it with the red and blue hoses
=> Red hose and blue Hose fill in 1 min = 1/45
90 minutes to fill it with red and green
=> Red Hose & Green Hose fill in 1 min= 1/90
Red Hose , Green hose & Blue hose in 1 Min =
Red Hose & Green Hose + Red hose and blue Hose - Red hose in 1 min
= 1/45 + 1/90 - 1/180
= ( 4 + 2 - 1)/180
= 5/180
= 1/36
Red Hose , Green hose & Blue hose in 1 Min = 1/36
=> Red Hose , Green hose & Blue hose will fill in 36 Minutes