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!

Do images move faster than objects?

  1. Sep 10, 2013 #1
    1. The problem statement, all variables and given/known data

    A cat sees its image in a plane mirror. The cat is 1 m from the mirror. A) Where is the image? B) The cat lunges at the mirror at 2 m/s. How fast does the cat approach its image?


    3. The attempt at a solution

    I understand that for a, the image would also be 1 m away from the mirror. I thought this would be the case for 2B too, that the image would move as fast as the object was found its image would actually move 4 m/s. I don't understand why this would be the case...Any input on this would be appreciated.
     
  2. jcsd
  3. Sep 10, 2013 #2
    The image indeed moves with 2 m/s but with respect to the mirror. So what is the relative velocity between cat and its image?
     
  4. Sep 11, 2013 #3
    The cat is moving toward the mirror cat, and the mirror cat is moving toward the cat. Think of it as two cars about to collide.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted