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Homework Help: Homework help-DC Circuits

  1. Feb 24, 2004 #1
    Someone please help me out with this problem, I can solve for the current but from there i get stuck...

    A solar cell generates a potential difference of 0.10 V when a 600 resistor is connected across it, and a potential difference of 0.15 V when a 1150 resistor is substituted. What are
    (a) the internal resistance and

    (b) the emf of the solar cell?

    (c) The area of the cell is 2.0 cm2, and the rate per unit area at which it receives energy from light is 2.0 mW/cm2. What is the efficiency of the cell for converting the light energy to thermal energy in the 1150 external resistor?
  2. jcsd
  3. Feb 25, 2004 #2


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    Homework Helper

    The best thing to do is solve these two simultaneously (2 eqs. and 2 unkwns.). Can you please describe how you are modelling your circuit?

    You need to know the definition of efficiency, and how to find the power delivered to the load resistor. Do you know these two things?
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