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Maybe this is too simple 4 u guyz

  1. Feb 28, 2004 #1
    but we get off homework for 3 weeks if 1 of us gets the answer by 9 am on Monday! yippeee

    A mass of 10kg lies on a smooth plane which is inclined at xº to the horizontal. The mass is 5m from top measured along the plane. One end of a light inextensible string is attached to the mass. The string passes up the line of greatest slope and over a smooth pulley fixed at the top of the plane. The other end is attached to a freely suspended 15kg mass. This mass is 4m above the floor. The system is released from rest, and the string first goes slack 1 and 3/7 seconds later

    Find the volume of xº

    any help will be greatly accepted!!

  2. jcsd
  3. Feb 28, 2004 #2
    As for the question: Huh? Volume of x0?

    As for whether or not anybody should answer the question: What do you have against homework? It's either do homework or do crappy on exams and have to do extra work to make-up the grade, no?

  4. Feb 29, 2004 #3
    Maybe you dont see it that way when youre 13 and the whole class is to get off -not just you=

    But thanks anyway -Cool site, hopefully I'll be back again (when I get all my homework done heheeee


  5. Feb 29, 2004 #4


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    Homework Helper

    Well I'm not just going to answer someones homework unless I can IM them and get them to work it out step by step.

    However here is a nice Website: http://www.mathsnet.net/ for maths help.

    I do believe the sort of examples of questions that you want will be somewhere in this section: http://www.mathsnet.net/asa2/modules/m1.html

    Also I think you mean the angle of x, not the volume.
  6. Feb 29, 2004 #5
    Thnaks for those links! Much appreciated.

    Just to clear up one thing.

    - This test was NOT HOMEWORK - I do that myself all the time.

    This was a question way ahead of what we are doing in school - which the teacher gave us on Friday.

    and He said that if the right answer was in by Monday Morning - The whole class would get off Home work for 3 weeks

    So my guess is that it must be a trick question cos that could never happen.

    So I thought i'd ask you guys.

    I'm in Derry in Ireland by the way and really say thanks for the answers
  7. Feb 29, 2004 #6
    By the volume of x0 do you mean the angle? If so, after I finish my own hw I will put my hand to it, shouldn't be too hard.
  8. Feb 29, 2004 #7
    Well i wrote it down a volume - but clearly it has to be angle/degree


    I will check in - in the morning b4 school

    but no worries if ya can't - and mega thanks for even replying

    go raibh míle maith agaibh

    to you and all
  9. Feb 29, 2004 #8
    Refer to the diagram where needed.

    an aside to find a
    plug a in

    x=30 degrees

    And that is the answer I got: 30 degrees

    I did the work quickly though and there is a possibility I made a mistake, but with an answer that nice when taking into account 9.8 m/s^2 for gravity, I heartily doubt that I did

    If you have any questions about how I got it, just ask.

    edit: the diagram I made (a crappy one, though) was too large to attach. I merely made a right triangle of angle x, with a pulley at the other angle, the two attached blocks (the only important distance being the one block's 4 meters) and noted that only a portion of gravity pulls on the block.
    And btw, since no information about it was given, I ignored all forms of resistance, and angular momentum.
    Last edited: Feb 29, 2004
  10. Feb 29, 2004 #9
    depends how proficient you are :) (in this case he should probably do his homework though)
  11. Feb 29, 2004 #10
    Typically, the people that want to get out of homework are the ones that need it the most.

  12. Mar 1, 2004 #11
    Just wanna say a sincere THANK YOU to Wooh for taking thetime and effort to reply.

    You are a 'star'. Thanks again

    cookiemonster got the wrong end of the stick entirely and obviuosly did not read correctly the earlier posts and sadly seemed a little bitter and the end of it all.

    all should have the generocity of spirit of Wooh.

    life is too short...
  13. Mar 1, 2004 #12
    Did you get it correct? Did he accept? That's good, but I hope you understand HOW I did the problem, and you should still prep for tests!
    As far as cookie goes, his point is a good one! Don't be naive, studying is important, and, especially as you gravitate closer towards your college experience, homework will become more about preparation than menial tasks which yield menial grades. You are doing him a disservice if you think he was meanspirited, more I think he simply meant that the kinds of people who most want to avoid homework, are the ones who could benefit from a bit of studying, but IMHO that is your choice to make, and if you DO blow the next 3 weeks because of this, learn from him! But I sincerely doubt that will happen, so kudos, understand the problem, and succeed.
  14. Mar 1, 2004 #13
    It's nice when other people will defend you for you. Saves all sorts of work.

    Thanks, Wooh.

  15. Mar 1, 2004 #14
    *academic high five*
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