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Homework Help: Shopping Cart on an Incline

  1. Nov 23, 2008 #1
    A shopper pushes a 7.5kg shopping cart up a 13 degree incline.



    I need to find the force required to give the cart an acceleration of 1.41m\s\s up the incline.



    ive tried breaking the weight, force and acceleration into components but i just end up getting more confused....any help on this would be great, thanks for your time.
     
  2. jcsd
  3. Nov 23, 2008 #2
    F=ma

    If it was on level ground and you wanted it to go at 1.4ms-2, the force needed would be just 7.5*1.4=10.5N

    Now because it's on an incline you have to add in that component also. This diagram should explain it:

    http://instruct.tri-c.edu/fgram/web/Image86.gif [Broken]

    You need to counteract the mgsin0 by supplying that force in the opposite direction - up the slope.

    So that is 7.5*9.8*Sin13 = 16.53N

    Add the two together and you get 27.03N

    Eamon
     
    Last edited by a moderator: May 3, 2017
  4. Nov 23, 2008 #3
    Wow, now i understand! thanks so much for your help!
     
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