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Math Help - adding vectors

  1. #1
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    adding vectors

    adding vectors-2rdjgy0.jpg

    Ok, so I spent like 15min on this and I got no luck -_- some help on how to do this question, plz and ty
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  2. #2
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    For each of the 3 vectors you are given r and \theta

    First of all, convert them back to cartesian co-ordinates.

    x = r \cos \theta

    y = r \sin \theta
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  3. #3
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    Here is what I did. (after taking another 15min lol)

    I found out the x-coord's and y-coord's for each. Added them all up. Then I found the Rx and Ry, then I found the angle and magnitude.

    My anwer for angle waws -8.6, and the magnitude was 20.1
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  4. #4
    MHF Contributor Unknown008's Avatar
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    You need to say the from where you are measuring the angle. If you measure it from the x direction, you'll need 180 - 8.6 = 171.4 and since it is anticlockwise, you say that it's -171.4 degrees from the x axis.

    I got slightly different answers. (20.0 N for magnitude and 8.7 degrees in your answer. Maybe you rounded off your numbers?)
    But I think it's okay.
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