1. Limited time only! Sign up for a free 30min personal 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!

Homework Help: Converging lenses

  1. Jul 21, 2013 #1
    1. The problem statement, all variables and given/known data

    An object is in front of a converging lens with a focal length of 11.0 cm. The lens
    produces a real image located 25.0 cm from the lens. If the lens is replaced by a new lens
    (in the same position) that has a focal length of 32.0 cm, what is the image distance of the
    new lens? Is the image real or virtual?

    2. Relevant equations

    Thin lens equation

    3. The attempt at a solution

    lens 1:






    Virtual image
  2. jcsd
  3. Jul 21, 2013 #2


    User Avatar
    Homework Helper
    Gold Member

    Your approach is correct.

    Your answer is pretty close, but there are some rounding errors. You might want to try again, but keep more significant figures in the intermediate steps.
  4. Jul 22, 2013 #3
    I got -.509 on the second try. Hopefully that is correct.
  5. Jul 22, 2013 #4


    User Avatar
    Homework Helper
    Gold Member

    Yup. :approve: (Don't forget your units though.)
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted