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Sources of light

  1. Oct 23, 2007 #1
    how do i measure the intensities of different sources of light?
    eg. candle light, tungsten filament etc.
  2. jcsd
  3. Oct 23, 2007 #2
    You must have at least two things : first, something that can direct light from the source to the cell and secondly the cell (sensor) that can convert light into electricity.
    The 1st part can be made very simply as a narrow tube which is long enough so the sensor can only receive light from the source.
  4. Oct 23, 2007 #3

    Claude Bile

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    Science Advisor

    Be careful with your quantities here.

    Intensity = W/sr
    Irradiance = W/m^2 (at the observer)
    Radiant Emittance = W/m^2 (at the source)

    Which specifically do you want to measure (I'm guessing Irradiance).

  5. Oct 23, 2007 #4
    Claude, that's an unusual set of definitions, you should consider calling W/sr "radiant intensity" to distinguish it from the notion of "intensity" that is normally used in at least early undergraduate physics.
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