Results 1 to 2 of 2

Math Help - Physics Question. I really need help with this!

  1. #1
    Newbie
    Joined
    May 2008
    Posts
    1

    Physics Question. I really need help with this!

    There is a very long steel bar with a regular pentagonal cross-section where each side of the pentagon is 2 cm in length. This bar will be suspended vertically over a very deep chasm. At the bottom end of the steel bar, there is a spherical steel weight with a diameter of 50 cm. Going up the bar, at every 3 metre increment, there is a spherical steel weight with a diameter of 30cm. If the density of the steel is exactly 7.8 g/cm3, the steel can withstand a tensile stress of 400 MPa, and gravity is 9.81m/s2, what is the maximum possible length, in metres, that the bar can extend without breaking?

    Can anyone help me out?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    10,070
    Thanks
    372
    Awards
    1
    Quote Originally Posted by silvernode View Post
    There is a very long steel bar with a regular pentagonal cross-section where each side of the pentagon is 2 cm in length. This bar will be suspended vertically over a very deep chasm. At the bottom end of the steel bar, there is a spherical steel weight with a diameter of 50 cm. Going up the bar, at every 3 metre increment, there is a spherical steel weight with a diameter of 30cm. If the density of the steel is exactly 7.8 g/cm3, the steel can withstand a tensile stress of 400 MPa, and gravity is 9.81m/s2, what is the maximum possible length, in metres, that the bar can extend without breaking?

    Can anyone help me out?
    Didn't you post this under another username here? If so, please don't double post.

    Anyway, I'm not going to type it all out again. I have answered this on PHF. (For those of you who are not silvernode, it's under "Urgent Homework Help.")

    -Dan
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Got a physics question or interested in physics?
    Posted in the Math Topics Forum
    Replies: 16
    Last Post: February 3rd 2014, 01:56 AM
  2. physics question
    Posted in the Math Topics Forum
    Replies: 3
    Last Post: October 25th 2009, 02:29 AM
  3. Physics Question
    Posted in the Math Topics Forum
    Replies: 2
    Last Post: October 17th 2009, 10:36 PM
  4. A physics question
    Posted in the Math Topics Forum
    Replies: 7
    Last Post: July 9th 2009, 03:34 PM
  5. Physics Question
    Posted in the Advanced Applied Math Forum
    Replies: 2
    Last Post: November 2nd 2007, 01:20 PM

Search Tags


/mathhelpforum @mathhelpforum