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Homework Help: Ramp Question

  1. Oct 14, 2005 #1
    http://img437.imageshack.us/img437/8104/untitled1wi.jpg [Broken]
    in 1 b) i know that the 4 N goes upwards

    but in questions like 1 d or e, whta do i do then
    for 1 d
    1) -mgsin30 is going down, ok
    and frictoin is going down, 2) -mgcos30u
    and the 8 N, is it 3) (8cos-30, 8sin-30)? if so, thats all good
    but i get confused is what do i do with all these terms now
    do i add them, 1) 2) 3) , i just wanted to know, the test is in an hour, need help asap :(
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Oct 14, 2005 #2


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    Science Advisor

    What exactly do you mean by "going down"? What you want to do is resolve the 8 N force into components parallel to and perpendicular to the ramp. The "8N" force will have components 8 cos(30) N up the ramp and
    8 sin(30) N into the ramp. You will probably also want to calculate the component of weight into the ramp so you can use the sum of those two forces into the ramp to find the friction force (which is, of course, back down the ramp). The component of weight parallel to the ramp will be back down the ramp and it, along with the friction force, will subtract from the component of the 8 N up the ramp.

    Last edited by a moderator: May 2, 2017
  4. Oct 14, 2005 #3
    i mean going dwon the x-y axis
    u kow when u write up the ramp as a x-y axis
    can you show me the final formula, of jsut one and how u arrived on the final answer, ill never get it until i see one
    got all weekend tho thats good
  5. Oct 15, 2005 #4
    any help ppl
  6. Oct 15, 2005 #5


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    Homework Helper

    I'm not understanding what you are doing. In what questions do you hae problems, and what were your attempts?
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