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Homework Help: Vector Addition

  1. Mar 4, 2008 #1
    [SOLVED] Vector Addition

    1. The problem statement, all variables and given/known data
    Find the angle between two vector forces of equal magnitude, such that the resultant is one-third as much as either of the original forces.

    2. Relevant equations
    Pythagorean Theorom, I assume

    3. The attempt at a solution
    This is from Schaum's 3000 Problems in physics, page 7, # 1.35... I don't understand their explanantion thus I dont understand where to begin. Can someone give me a lead?

    The answer is 160.8 degrees by the way...
    Last edited: Mar 4, 2008
  2. jcsd
  3. Mar 4, 2008 #2
    First off, lets state the Pythagorean Theorem as a^2 + b^2 = c^2. Cool.

    Next since we are using that equation we know that the answer involved has a right angle it it somewhere.

    Draw a picture of a right triangle then make it into a rectangle. Draw a line from corner to corner and going threw the other side(the size where the first right angle was)
    http://img182.imageshack.us/img182/3530/pythaghelpvw8.png [Broken]

    Then play around with the numbers and angles and see if you can come up with the same answer. I hope this helps you out a little bit! Although I am not exactly sure on how to solve it myself.
    Last edited by a moderator: May 3, 2017
  4. Mar 4, 2008 #3
    I don't have a program that can do any of that stuff?(like the diagram you just did)
  5. Mar 4, 2008 #4
    Dont you have pen and paper? I did that on my paper before I made it with photoshop o_O
  6. Mar 4, 2008 #5
    I've figured it out :D Thanks. I simply formed a parallelogram and was able to get the answer.
  7. Mar 4, 2008 #6
    No prob, Glad you got it!
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