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: Convex mirror. 2 objects

  1. Apr 9, 2009 #1
    1. The problem statement, all variables and given/known data
    An object is located 14 cm in front of a convex mirror, the image being 7 cm behind the mirror. A second object, twice as tall as the first one, is placed in front of the mirror, but at a different location. The image of this second object has the same height as the other image. How far in front of the mirror is the second object located?

    I know I need to use the mirror equation... but I am totally LOST!!
  2. jcsd
  3. Apr 9, 2009 #2


    User Avatar
    Homework Helper

    First of all find the focal length of the convex mirror and magnification. In this problem magnification v/u = 1/2 = I/o. When the When the size of the object doubles keepin image height the same. magnification becomes 1/4.
    So V'/U' = 1/4. Write V' in terms of U', substitute in the mirror formula to get U'
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook