Hi

How would I do this question:

Water is running into a conical reservoir, 15 m deep and 8 m in diameter at the top at the rate of 1 cubic m/min. What is the depth when the level is rising 9/32pi m/min?

Thanks a lot.

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- Apr 9th 2010, 01:17 AMSunyataRates of Change
Hi

How would I do this question:

Water is running into a conical reservoir, 15 m deep and 8 m in diameter at the top at the rate of 1 cubic m/min. What is the depth when the level is rising 9/32pi m/min?

Thanks a lot. - Apr 9th 2010, 01:45 AMICanFly
Sorry, this "9/32pi m/min" is velocity? Level of velocity?

- Apr 9th 2010, 01:50 AMArchie Meade
Hi Sunyata,

Write r in terms of h.

If you split the cone vertically, you have a right-angled triangle,

height H=15 and width R=4.

Hence

As the water flows in, the height and radius of the water vary, but they

still have the same ratio

Hence

As the water enters at per minute

Now substitute your value for

to find "h squared" and take the square root.