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Electric forces and Electric fields question on x and y components

  1. Jul 21, 2011 #1
    1. The problem statement, all variables and given/known data

    please see the pictures!

    2. Relevant equations


    3. The attempt at a solution

    okay, I am just curious as to why t cos theta and mg are x components when they are clearly on the y axix!
    I thought you used cos for x components and sin for y components

    Attached Files:

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  2. jcsd
  3. Jul 21, 2011 #2
    guys I know im a DA, i barely got by in physics I and I was able to get by without knowing how to do these type of problems, now I cant plz help!
  4. Jul 21, 2011 #3
    The cosine of theta is the adjacent side of the triangle divided by the hypotenuse. With theta defined to be where it is in this problem, T cos theta is the vertical component of the tension.
  5. Jul 22, 2011 #4
    Where is it written that they are on X axis .... looks on Y to me
    Maybe they took X as Y and Y as X

    OP's asking why the vertical component is called X component
    read question again
  6. Jul 22, 2011 #5
    I already read the question and the images about ten times before answering. It sounds to me like a teacher may have pounded it into the student's head that x means horizontal and then always take the cos, y means vertical and then always take the sin. I have heard some teachers say that, although it is wrong. The cure for the confusion is to identify the triangle and remember the "sohcahtoa" definitions of sin and cos.
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