Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Angle with respect to x or y axis.

  1. Oct 3, 2006 #1
    Could anyone please tell me what angle I need to find when the question asks to find an angle with respect to x axis. (or y axis)
    Thank you.
     
  2. jcsd
  3. Oct 3, 2006 #2
    with respect to the x or y: let's say that your angle is in 2-space or a 2-d angle. If you want to measure it with respect to the x axis it means that you start on the x - axis and move counter clockwise to your angle. the same logic is used for the y as well
     
  4. Oct 3, 2006 #3
    Which side of x-axis (positive side or negative side) should I choose to start moving counter clockwise to my angle?
     
  5. Oct 3, 2006 #4
    usually it is the positive side
     
  6. Oct 4, 2006 #5
    A question tells me to find an angle of a vector F with respect to positive x-axis.

    Suppose the vector F points 17.1 degrees west of north. Then if I were to find angle of this vector with respect to positive x-axis, I add 17.1 degrees and 90 degrees and get 107.1 degrees, right?
    On a question that asked to find the angle with respect to positive x-axis, I solved it as stated above, but it's wrong.
    What is wrong with my method?
     
  7. Oct 4, 2006 #6
    your angle is in the second quadrant. so you should do this 180-17.1 = 162.9 degrees.
     
  8. Oct 4, 2006 #7
    I tried 162.9 degrees but I was told it's wrong. It's very frustrating.. :(
    The question should explain what it means by "with respect to positive x-axis".
    What should I do?
     
    Last edited: Oct 4, 2006
  9. Oct 4, 2006 #8
    I still don't get this. Please tell me how to do this.
     
  10. Oct 5, 2006 #9
    Now I got it. I had made a small mistake.
    Mesmer, thank you for your help. =)
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook