Results 1 to 4 of 4

Math Help - Momentum

  1. #1
    Junior Member
    Joined
    Oct 2007
    Posts
    69

    Momentum

    An animal-rescue plane flying due east at 23 m/s drops a bale of hay from an altitude of 60 m.

    The acceleration due to gravity is
    9.81 m/s^2

    If the bale of hay weighs 177 N; what is the
    momentum of the bale the moment it strikes
    the ground? Answer in units of kgm/s.



    OK, I don't know what to do with this one. I use a kinematics equation to find the velocity when the bale hits the ground (I get Vf = 34.31m/s) and then I divide the 177N by 9.81 to get it's weight in kg. I multiply that mass by the Vf to get 619, but apparently that answer is wrong. Any insight?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    o_O
    o_O is offline
    Primero Espada
    o_O's Avatar
    Joined
    Mar 2008
    From
    Canada
    Posts
    1,407
    Remember, momentum is a vector. It has both a horizontal and vertical component (assuming no air resistance). Find the resultant velocity by pythagoras seeing you know both componential velocities (and find the direction if you need it). Then, calculate the momentum \vec{p} = m\vec{v} where m can be found, as you've said, by its weight.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Oct 2007
    Posts
    69
    RIGHT! I should've known there was something wrong with that, thanks for adding in the missing piece
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    9,852
    Thanks
    321
    Awards
    1
    Or you could find the final velocity directly by using conservation of energy.

    -Dan
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Total Momentum?
    Posted in the Algebra Forum
    Replies: 2
    Last Post: October 9th 2009, 06:52 PM
  2. Momentum
    Posted in the Math Topics Forum
    Replies: 2
    Last Post: May 19th 2009, 10:59 PM
  3. momentum
    Posted in the Advanced Applied Math Forum
    Replies: 1
    Last Post: December 9th 2008, 02:57 AM
  4. momentum
    Posted in the Advanced Applied Math Forum
    Replies: 1
    Last Post: May 2nd 2008, 01:57 PM
  5. Momentum
    Posted in the Math Topics Forum
    Replies: 3
    Last Post: October 27th 2007, 02:50 PM

Search Tags


/mathhelpforum @mathhelpforum