Results 1 to 3 of 3

Math Help - refraction

  1. #1
    Newbie
    Joined
    Mar 2009
    From
    Lucknow
    Posts
    13

    refraction

    A ray of light is sent along the line x-2y=8. After refraction across the line x+y=1 it enters the opposite side after turning by 15degrees away from the line x+y=1. find the equation of the line along which refracted ray travels.
    please solve step by step.
    and is there any standard method of doing these types of questions(refraction as well as reflection)?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Junior Member JoanF's Avatar
    Joined
    Apr 2009
    Posts
    39
    Hi!

    I did but I don't know if it is correct, could you give me the solution of the problem?
    Are you sure that it is about refraction? Or is it about reflection??

    I think you've to do this using the slope of the lines:
    x+y=1 <=> y=1-x
    so you know that the slope of this line is -1, and then you can use trigonometry: tg alfa = slope of the line <=> tg alfa = -1 <=> alfa = 135

    you said "it enters the opposite side after turning by 15degrees away from the line x+y=1", so you do: 135+15=150

    and then you have that the slope of the new line is tg 150
    and the equation of the new line is: y=tg 150x+1
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by Gaurav View Post
    A ray of light is sent along the line x-2y=8. After refraction across the line x+y=1 it enters the opposite side after turning by 15degrees away from the line x+y=1. find the equation of the line along which refracted ray travels.
    please solve step by step.
    and is there any standard method of doing these types of questions(refraction as well as reflection)?
    The intersection of the lines x - 2y = 8 and x + y = 1 gives you a point on the line of refraction.

    You know the gradient of the line x + y = 1. and you're given the angle between the line of refraction and the line x + y = 1. So use the formula for the angle between two lines to get the gradient of the line of refraction.

    Now you have a point and you have a gradient. So get the equation of the line.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Refraction!!!
    Posted in the Math Topics Forum
    Replies: 3
    Last Post: July 6th 2010, 08:05 PM
  2. Refraction and reflection
    Posted in the Math Topics Forum
    Replies: 0
    Last Post: May 18th 2009, 07:14 PM
  3. Refraction
    Posted in the Math Topics Forum
    Replies: 2
    Last Post: May 17th 2009, 11:00 PM
  4. Angle of Refraction
    Posted in the Pre-Calculus Forum
    Replies: 1
    Last Post: September 1st 2008, 03:31 AM
  5. refraction of light
    Posted in the Advanced Applied Math Forum
    Replies: 1
    Last Post: August 30th 2007, 08:17 PM

Search Tags


/mathhelpforum @mathhelpforum