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!

Pinhole Camera

  1. Feb 26, 2006 #1

    G01

    User Avatar
    Homework Helper
    Gold Member

    A point source of light 2.0m away from the a pinhole camera creats a 12cm wide spot of light on the screen 1.0 deep inside the camera. How wide is the aperture of the camera.

    I thought this was a magnification problem, so I set up the equation:

    [tex] h_i = .12m, h_o = x, s_i = 1m, s_o = 2.0m[/tex]

    [tex] \frac{h_i}{h_o} = \frac{s_i}{s_o}[/tex]

    [tex] \frac{.12m}{x} = \frac{1m}{2m}[/tex]

    [tex].24m = x [/tex] The answer is .08m. I'm getting many of these optics problems wrong and I don't know why. I need some help and several of the problems I have posted have gone without answers. I hope someone answers this one. Thank you for your help.
     
  2. jcsd
  3. Feb 26, 2006 #2

    Tide

    User Avatar
    Science Advisor
    Homework Helper

    The numerator on the right side should be 3 meters. You're trying to set up a proportion but you're not equating the correct ratios.
     
  4. Feb 26, 2006 #3

    G01

    User Avatar
    Homework Helper
    Gold Member

    Yes, I just realized this, that should be 3/2 not 1/2. Screwed up my similar triangles.... Thank you so much..
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Pinhole Camera
  1. Pinhole camera. (Replies: 2)

  2. Pinhole Camera (Replies: 4)

Loading...