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Element absorbing/supplying power?

  1. Sep 10, 2011 #1
    Hello, I am working on some basic circuit problems. I am just getting started and am having some difficulties with the wording of the problems. For example, a problem shows that 4 A of current is entering the negative terminal of an element with potential of +20 V, where I then have to calculate the power being absorbed by the element. This seems odd to me, if the potential is +20 V, then the positive terminal of the element has a higher potential compared to the negative terminal, specifically, with a magnitude of 20 V, right? So if current flows through the element in from the negative and out through the positive, aren't the electrons gaining energy as they pass through it, which means that the element is supplying energy to the circuit? Does the question imply that the element is absorbing power from its surroundings, like a battery charger or something?
     
  2. jcsd
  3. Sep 10, 2011 #2
    For the problem you described, you may answer that the power absorbed is negative.
     
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