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What happens to projected light after the source stops

  1. Nov 6, 2015 #1
    Let's say a flashlight or a laser is turned on and there's light coming out of it. Once you turn the flashlight or laser off what exactly happens to the projected light? Obviously it won't be visible anymore, but where does it go?
  2. jcsd
  3. Nov 6, 2015 #2
    Simply put, it's absorbed by the objects surrounding it.
  4. Nov 6, 2015 #3
    Ok now I get it. Thanks
  5. Nov 6, 2015 #4
    The energy of the light is transferred to the atoms it comes in contact with, if it does... they then might pass on that energy in different ways. light, heat, etc.
  6. Nov 6, 2015 #5


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    Perhaps the light gets absorbed, perhaps not. Remember, light travels at 300,000 km / sec, so who's to say the light sticks around to get absorbed? By the time you'd notice the beam is shut off, the last photons have almost reached the orbit of the moon. :wink: :eek:
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