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Homework Help: Fluid questions.

  1. Nov 18, 2004 #1
    Hey! I have been out of school sick for a week! I'm a little behind and having some trouble understanding some things. Here is a question that has me stumped.

    An Amusement park is planning to build a water slide, and the park owners would like to use big giant corks (p= 0.28g/cm^3) as "floats" for young children. what volume of cork is need to keep 20 percent (by volume) of a 40kg child above water at the base of the slide(assume the density of the child is 1.01g/cm^3)?

    I found that the 20% of 40kg = 8kg
    and i found that the density of the child = 7.9207
    Last edited: Nov 19, 2004
  2. jcsd
  3. Nov 18, 2004 #2
    Another that has me stumped in this section is:

    when you take your car into the shop to have it worked on, a hydraulic lift is used. The diameter of the piston lifting your car and the base it sits on have a combined mass of 12000kg. the oil used in this lift has a density of 800kg/m^3.

    A. How many apples would you need to place on the imput piston in order to hold up your car? A medium apple weighs approximately one newton. :confused:
    B. When the car reaches a height of 0.15m, how many apples will it take to support the car at that height? :confused:

    I don't even know where to start,i don't even know what they are talking about??
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