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Homework Help: Half wave rectifier proof

  1. Jan 14, 2010 #1
    1. The problem statement, all variables and given/known data
    How to prove that Vrms = 0.5 Vmax for half wave rectifier


    2. Relevant equations



    3. The attempt at a solution
    I know the graph of half wave rectifier is just the upper part or lower part of sinusoidal wave. But I don't have clue to prove it..

    Thanks
     
  2. jcsd
  3. Jan 15, 2010 #2
    So that means that for a half-wave rectifier you can define voltage as a piecewise function of time:
    [tex]
    V(t) = \left\{ \begin{array}{cc}V_{max}sin({\omega}t),&\mbox{ if } 0 \leq t \leq \frac{T}{2}\\0,&\mbox{ if } \frac{T}{2} < t \leq T\end{array}\right.
    [/tex]

    And it's a fairly straightforward calculation to find the RMS value of the function:
    [tex]
    \sqrt{\frac{1}{T}\int_{0}^{T}[V(t)]^2dt[/tex]
     
  4. Jan 15, 2010 #3
    I get it now

    Thanks a lot, JaWiB !! :smile:
     
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