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Homework Help: Overall power in Nd/YAG laser

  1. Nov 28, 2012 #1
    1. The problem statement, all variables and given/known data

    In the units of watts (J/s) calculate the overall power of the laser light generated by Nd/YAG laser operating with a 10 Hz repetition rate in the third harmonic (355nm) at 150mJ per pulse

    2. Relevant equations
    I cant figure out how to do this problem see attempt below:

    3. The attempt at a solution
    I know the following:
    Power= E/t=J/s=watt
    E=(Hz)(6.626E-34 J/s)
  2. jcsd
  3. Nov 29, 2012 #2
    ok so I think i figured it out

    t=0.1 sec

    E=150mJ/0.1 sec
    E=1.5 J/s

    is that correct?
  4. Nov 29, 2012 #3


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    I think so, but note that you used E for energy in the statement of the problem and now you're using E for power.
  5. Nov 29, 2012 #4
    ah yes you are correct, it should of been P=W/s not E
  6. Nov 29, 2012 #5


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    Yes, P for power. But now your units aren't correct if W is watts. 1W = 1 J/s. (or is W for "work"?)
    Last edited: Nov 29, 2012
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