Results 1 to 2 of 2

Math Help - Volume of a cone

  1. #1
    Junior Member
    Joined
    Oct 2008
    Posts
    34

    Volume of a cone

    A cone is formed by rolling up a 90 degree sector of a circle having a radius of 8 inches. Find the volume of the cone to the nearest tenth

    l is equal to 8. I am having a problem finding the radius and the height. I want to say the lateral area and the base form a 60 degree angle, I am not told this so do not want to assume anything. Help to figure out how to start of where to start would be great thanks.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Member
    Joined
    May 2009
    Posts
    127
    You can work out the radius, r, of the cone from the circumference formed when the sector is folded around. So use the given radius, R, and the angle given to work out the length around the edge of the sector and that will be the circumference of the base of the cone.

    Then use the Pyathagoras' theorem with R and r to work out the height.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 1
    Last Post: May 14th 2010, 04:08 PM
  2. volume of a cone
    Posted in the Geometry Forum
    Replies: 1
    Last Post: April 2nd 2010, 11:17 AM
  3. Volume of a cone
    Posted in the Algebra Forum
    Replies: 1
    Last Post: January 8th 2010, 11:44 AM
  4. volume of cone
    Posted in the Geometry Forum
    Replies: 2
    Last Post: May 27th 2008, 09:27 AM
  5. Volume of a cone
    Posted in the Geometry Forum
    Replies: 7
    Last Post: April 21st 2008, 04:57 AM

Search Tags


/mathhelpforum @mathhelpforum