Engineering Board Exam Reviewer · RC Circuits · easy

If the source frequency of a series RC circuit is doubled while R and C are unchanged, the capacitive reactance

  1. is doubled
  2. is halved
  3. stays the same
  4. is quadrupled

Answer

B. is halved

Solution

XC=1/2π fC is inversely proportional to frequency, so doubling f halves XC.

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