Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Light source

  1. Nov 14, 2007 #1
    what do we mean when we say a point light source is [tex]5.0 mW[/tex]
    Last edited: Nov 14, 2007
  2. jcsd
  3. Nov 14, 2007 #2


    User Avatar
    Science Advisor
    Homework Helper

    That is an energy - so not very useful, unless it means 5.0mJ/s ie 5milliWatts.

    In astronomy it could be a typo for mJy = milli Jansky bit this isn't commonly used for visible light
    Last edited: Nov 15, 2007
  4. Nov 14, 2007 #3
    sorry that was watt.
  5. Nov 15, 2007 #4

    Shooting Star

    User Avatar
    Homework Helper

    It's not energy, it's power. It means the light source is giving out energy at the rate of 5 J/s.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook