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Light Mass

  1. Mar 28, 2007 #1
    I am a lower sixth student and i got into an argument with my physics teacher today when we were talking about the photovoltec effect and he said that light has no mass. I have a very small understanding of the subject compared to him but from what i do understand the uncertanty principle states that light can change the momenteum of something and so it must have mass to have momentium. Also i know that gravity can bend light and this also points out that it must have a mass. His response was that light is just energy until it hits something and then it changes its energy to mass.
    I cannot grasp the concept of something existing of pure energy i was wondering if somebody could shed some light on this. Thanks
  2. jcsd
  3. Mar 28, 2007 #2


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    I recall a new addition to the FAQ regarding this a few days ago. Here's the link: https://www.physicsforums.com/showpost.php?p=1285138&postcount=6 [Broken]
    Last edited by a moderator: May 2, 2017
  4. Mar 28, 2007 #3
    Thanks, i understand it now.
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