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    Here is the question:

    Find the magnitude of the resultant and the angle the resultant makes with the positive x-axis for the following forces.

    (Image)


    I know how to get the resultant force.. 6.7
    It's just the angle the puts me off. I get 26.6.
    But on the answer book they have 206.6.

    They added 180 on. It's the "Find the angle with the positive X-axis that confuses me"

    Any ideas??
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    You're finding the angle with the negative x axis (which is pointing in the same direction as the 6 force). However they want the angle with the positive x axis which points in the other direction.
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    (Original post by ttoby)
    You're finding the angle with the negative x axis (which is pointing in the same direction as the 6 force). However they want the angle with the positive x axis which points in the other direction.
    Thanks for replying,

    How did they get 206.6 then?
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    (Original post by CtrlAltDefeat)
    Thanks for replying,

    How did they get 206.6 then?
    It's wrong. 206.6 would be the angle, clockwise, from the positive y.
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    (Original post by CtrlAltDefeat)
    Thanks for replying,

    How did they get 206.6 then?
    Sorry I tried to reply earlier but then the website hanged and I forgot about it. 206.6 is correct.

    Imagine you're pointing in the positive x direction (to the right). Then turn anticlockwise 180 degrees to point in the negative x direction. Then turn another 26.6 degrees anticlockwise until you're pointing in the direction of the resultant force. So the force is 180+26.6=206.6 degrees anticlockwise from the positive x axis.
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    hi,
    i had the same problem, with the same question.

    the positive x-axis is where zero degrees begins and you have to go round anticlockwise to complete the full 360 degrees turn.

    the question is asking about the angle the resultant makes with the positive x-axis.

    therefore, alone, the angle of the resultant force is 26.5 or something. but with the positive x-axis, you have to add on 180, in order to reach the resultant force form the positive x-axis.

    which means that the angle made with the positive x-axis is 206.

    try drawing it and dot the positive x-axis and then trace the angle it from that axis all the way till the angle of the resultant force. thats what its asking you to find.

    im sorry, im not good at explaining things well, but i thought id try because it took me a lot of time to get my head around this too.

    good luck!
 
 
 
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