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Homework Help: Recording power and lumens for light bulbs.

  1. Mar 27, 2008 #1
    1. The problem statement, all variables and given/known data
    Which is more efficient, or has the highest lm/W, a lower- or higher-power light bulb? To find out, look at bulbs and record the power and lumens.

    2. Relevant equations
    Lumen, lm, = P or luminous flux.

    3. The attempt at a solution
    Power of the light bulbs would be the number of watts, correct?
    I am confused as to how to calculate the lumens of a light bulb. My teacher said that we can just look at bulb boxes at a store, so I know no measuring of surfaces is involved.

    Thanks in advance.
  2. jcsd
  3. Mar 27, 2008 #2
    In europe, the number of Lumen will be present on the box.
    I Have 2 boxes here that say:
    230 V, 60 W, 710 Lumen
    230 V, 100 W, 1340 Lumen
    Kind of bulb: "Pearl"
    so I don't think there is any calculation involved. I'd try to get some more datapoints
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