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

Co-ordinate Geometry

  1. Dec 14, 2008 #1
    Co-ordinate Geometry (Circle problem)

    I've a small Query.
    Suppose a circle is plotted with its center at distance h,k (from x=0, y=0) with radius R. If theta is an angle from h,k to any point over the circle, we know that the co-ordinate of that point, from (h,k) perspective, will be Rcos(theta),Rsin(theta). In such a case, what shall be the co-ordinate of the SAME POINT, if it is taken from x,y.
    [​IMG]
     
    Last edited: Dec 15, 2008
  2. jcsd
  3. Dec 15, 2008 #2

    CompuChip

    User Avatar
    Science Advisor
    Homework Helper

    Welcome to PF ad_bose.

    May I suggest vector addition?
    Let c be the vector from the origin to the center of the circle, and p the point on the circle with respect to the center. Then the vector P of the point on the circle with respect to the origin is ... ?
     
  4. Dec 15, 2008 #3
    Thanks for your suggestion. My query is simple.

    The given parameters are :
    1. R = Radius of the circle
    2. h,k = the co-ordinates with respect to Origin (x,y = 0,0)
    3. [tex]\theta[/tex] - The angle from h,k along the x-axis to the mentioned point
    If the origin is fixed at x,y and is 0,0; what will be the x-distance and the y-distance of the point from Origin.

    I am actually preparing a computer program, in Embarcadero Delphi.
    The code is given in attachment. Any help is highly appreciated. I need to actually place an object over the circle from 0,0. Kindly see the code.
     

    Attached Files:

  5. Dec 15, 2008 #4

    CompuChip

    User Avatar
    Science Advisor
    Homework Helper

    As I said (or was trying to say), try adding h to the x-coordinate and k to the y-coordinate.
     
  6. Dec 15, 2008 #5
    Thanks pal, the Astrology program bug is solved.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?