This is a problem i just cant get my head around.(adsbygoogle = window.adsbygoogle || []).push({});

When you have a circuit consisting of a "Ideal Voltage source -> Ideal switch -> Ideal Resistance" all in series. The voltage source produces a sinusodal voltage and the switch is set to cut off a part of any rising curve:

http://img383.imageshack.us/img383/8819/picture2ixx.png [Broken]

Now if you do the calculations for the effective power that is dissapated at the resistance and the apparent power given off by the voltage source you will see that the apparent power is quite a bit higher than the effective power (P = 0.89*S for alpha = pi/3, (see picture)).

[tex]P_R = I_{eff}^2\cdot R, S = I_{eff}\cdot U_{eff}[/tex]

How does this happen? where is the reactive power going?

PS: I have done all the calculations, im not asking for those, im looking for an explanation. Thanks :)

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# Voltage source -> Ideal switch -> Resistance = Reactive power

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