Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Cone's volume, not seeing a step posted elsewhere

  1. Jan 29, 2009 #1
    Hey all,

    can you check out this site


    In the very first line of the integral, I'm not sure why it's squared, or why the x is there. Can someone explain this?
    Clearly, its correct because the correct answer is derived lol.

  2. jcsd
  3. Jan 29, 2009 #2


    User Avatar
    Science Advisor
    Homework Helper

    Hi Damascus Road! :smile:

    The cone is sliced into discs of thickness dx at height x.

    So the radius of each disc is x/h times the base radius (r),

    and the volume of the disc is that squared times π times dx.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook