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Qube
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Homework Statement
http://i.minus.com/jz5YbMhv91p6K.png
Homework Equations
Volume is the area of the base (or cross section) times height.
The Attempt at a Solution
The base is a triangle. The area of a triangle is (0.5)(base length)(height). In this case that's 0.5*20*15, or 10 times 15, or 150.
V = 150(h).
We differentiate volume with respect to time, since the problem gives us dV/dt and expects us to find dh/dt.
dV/dt = 150(dh/dt).
24 = 150(dh/dt)
The change in height with respect to time is 24/150 inches/second.
This is an unfamiliar problem and I am unsure if I proceeded correctly. Am I right? It seems as if the height variable disappeared; that h = 8 as stated in the problem is extraneous information and that the rate of height increase is constant. Intuitively, this feels correct. But is it?
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