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Diode in reverse bias

  1. Aug 21, 2010 #1
    In forward bias the supplied voltage is distribute among the resistor and the diode (diode and resistor are connected in series) but in reverse bias the Current across the resistor remain zero because the conduction starts when very high voltage is supplied ...am i right ?
    but why the Voltage across resistor and current across resistor remain also zero when resistor and diode are connected in series in Reverse Bias ??
  2. jcsd
  3. Aug 21, 2010 #2


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    You cannot have current across something. Your wording my have me confused. Ohms law can pretty much explain your question. In reverse bias prior to the diodes breakdown voltage no current is flowing so no voltage can develop across the resistor.
  4. Aug 22, 2010 #3
    i want to know why the voltage accross Resistor , current accross the resistor is zero in reverse bias ??
  5. Aug 22, 2010 #4


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    As ASN said you cannot speak of "current across" anything. Think of it as current through the resistor. The current through the resistor is zero because the total circuit current is zero (or at least VERY small). Since the current through the resistor is zero by Ohms law so is the voltage. Note that current through the diode is also zero.
    Last edited: Aug 22, 2010
  6. Aug 22, 2010 #5
    Thanks alot :)
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