# A closed conical vessel is filled with water fully and is placed with its vertex down. Thewater is let out at a constant speed. After 21 minutes it was found that the height of thewater column is half of the original height. How much more time in minutes does itrequire to empty the vessel?

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A closed conical vessel is filled with water fully and is placed with its vertex down. Thewater is let out at a constant speed. After 21 minutes it was found that the height of thewater column is half of the original height. How much more time in minutes does itrequire to empty the vessel?

## 7 Answers

7 years ago

let the height of cone be ‘h’ and radius be ‘r’

Volume of water is (1/3)r

^{2}h.After 21min height of water becomes ‘h/2’.Applying simiar trianles concept in the cone, we get new radius as r/2.

Hence remaining volume is (1/3)(r/2)

^{2}h/2=(1/3)r^{2}h/8.Then amount of water drained out is 7(1/3)r

^{2}h/8.Then time taken to empty the vessel =21×[(1/3)r

^{2}h/8]/[7 (1/3)r^{2}h/8]=3min.I’m sorry due to problems ,browser is showing “pi” as .

4 years ago

4 years ago