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Homework Help: What is the resistance of this device?

  1. Apr 5, 2004 #1
    Hello, I am stumped on this question from my text book:

    I tried by using this equation which I felt should work:

    But it doesn't seem to get me the correct answer (which is 22 ohms). Any ideas? Thanks!
  2. jcsd
  3. Apr 5, 2004 #2


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    [tex]P = \frac{V^2}{R}[/tex]

    [tex]R = \frac{V^2}{P}[/tex]

    [tex]R = \frac{1.5^2}{0.1}[/tex]

    [tex]R = 22.5 \Omega [/tex]

    Maybe the book is just wrong.
  4. Apr 5, 2004 #3
    Thank you very much! Yeah... the 22 answer probably has something to do with sig figs.
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