- Water is flowing at the rate of 15km/hour through a pipe of diameter 14 cm into a cuboidal pond which is 50 m long and 44 m wide. In what time the level of water in the pond rise by 21 cm?
Let the level of water in the pond rises by 21 cm in t hours.
Speed of water = 15 km/hr
Volume of water flowing out of the pipe in 1 hour
= π r2h
= 231 m3
∴ Volume of water flowing out of the pipe in t hours = 231 t m3.
Volume of water in the cuboidal pond
= 462 m3
Volume of water flowing out of the pipe in t hours = Volume of water in the cuboidal pond
∴ 231 t = 462
Thus, the water in the pond rise by 21 cm in 2 hours.