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Homework Help: Concept based light and optics ?

  1. Apr 26, 2008 #1
    1. The problem statement, all variables and given/known data

    When a gas is heated, it emits red and green light. What is its color when it is cool?

    What % of light is reflected from a normal window? (answer choices 0, 20, 50 and 100)

    2. Relevant equations


    3. The attempt at a solution

    For the first question, I can't think of any answer without knowing the element (it's not given).

    For the second question, I want to say 0% if it is 90 degrees to the window...but I'm clueless.

    Thanks for the help!
  2. jcsd
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