Engineering Board Exam Reviewer · Time Response of Reactive Circuits · medium

If the resistance in a series RC charging circuit is doubled while C is unchanged, the time constant

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

Answer

C. doubles

Solution

=RC is directly proportional to R, so doubling R doubles and the capacitor takes twice as long to charge.

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