1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Can Someone please explain what i'm looking for?

  1. Nov 17, 2005 #1
    You are trying to photograph a bird sitting on a tree branch, but a tall hedge is blocking your view. However, as the drawing shows, a plane mirror reflects light from the bird into your camera. If x = 3.1 m and y = 4.0 m in the drawing, for what distance must you set the focus of the camera lens in order to snap a sharp picture of the bird's image?


    Ok so all i need to find out is what exactly do they mean about setting the focus to get the sharpest picture...... am i just looking for the length of all of the red line? thats what i'm assuming but i want to be sure.... or is it just part of the red line??? anyone want to answer this simple question for me!?:biggrin:
  2. jcsd
  3. Nov 17, 2005 #2

    Doc Al

    User Avatar

    Staff: Mentor

    That's it. That's the distance the light travels from object to camera. You'll have to use your knowledge of the laws of reflection to find that distance.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?