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 Be the first pioneers to continue the Astronomy Discussions at our new Astronomy meeting place...The Space and Astronomy Agora Re: Re: Radius Of Curvature Forum List | Follow Ups | Post Message | Back to Thread Topics | In Response ToPosted by Tom Leech on November 8, 2000 21:33:20 UTC

if a photon.........hey rick, i think all the guy wants to know is what should be his radius of curvature for a given focal length. the answer is the radius of curvature is twice the focal length..... this can be seen if you place a small light at the radius of curvature , it will shine (focus) the light right back on itself. then if you begin to move the tiny light along the axis toward the mirror, it will focus the reflected image further and further away, until when you reached a point 1/2 the radius of curvature, the light will be focused at infinity, and the light beam leaving the mirror willbeaparallel (collimated) beam of light. if you draw yourself a picture, taking into account what rick said that the angle of entrance at a mirror surface is equal to the angle at reflectoin, you will see how this works if your drawing is carefully done. good luck with your curve generating. tom leech