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    Water is pumped into a conical tank at a rate of 0.3m3s-1. The tank has the dimensions shown in the diagram, and the depth of the water is h metres at time t seconds. find an expression for dh/dt

    the cone has diameter 4m, and height 8m overall. (sorry for lack of diagram, q is from textbook)

    I keep getting 0.9/pi r^2 for my expression but apparently this is wrong...

    Please help!
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    Well I make it \dfrac{9}{40\pi} Is that right?
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    (Original post by Gmart)
    Well I make it \dfrac{9}{40\pi} Is that right?
    no
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    (Original post by penelopecrux)
    Water is pumped into a conical tank at a rate of 0.3m3s-1. The tank has the dimensions shown in the diagram, and the depth of the water is h metres at time t seconds. find an expression for dh/dt

    the cone has diameter 4m, and height 8m overall. (sorry for lack of diagram, q is from textbook)

    I keep getting 0.9/pi r^2 for my expression but apparently this is wrong...

    Please help!
    You know that \frac{dV}{dt}=0.3

    Then this result can be given by \frac{dV}{dt}=\frac{dV}{dh}\cdot \frac{dh}{dt}
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    (Original post by RDKGames)
    You know that \frac{dV}{dt}=0.3

    Then this result can be given by \frac{dV}{dt}=\frac{dV}{dh}\cdot \frac{dh}{dt}
    YES i know that, I just dont understand why my answer is incorrect.
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    (Original post by penelopecrux)
    YES i know that, I just dont understand why my answer is incorrect.
    What's the 'official' answer then?
 
 
 
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