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With inductors quality is increasing with L and frequency and decreasing with R.

Quality is supposed to also tell us how much energy is stored in each cycle compared to how much is dissipated by resistance.

But when it comes to capacitors the quality decreases if we increase C. Is the energy stored higher if we have a smaller capacitor? This sounds very counter intuitive.

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As you go up in frequency with an inductor (or up in inducatnce) the impedance due to the inductance increases. this means more of the energy is put in the inductance and less in the R. With capacitor, as we increase C, the impedance lowers - this means that we have less energy in the C, and more gets wasted in the R. It's not so much that more energy is stored if we have a smaller capacitance, as you say, that would be counterintuitive. Rather, the ratio of energy in the electric field in the C to the energy in R increase.

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    \$\begingroup\$ As far as I see, the bigger the capacitor, the more energy can get stored in it at a given voltage. If we reduce C, the current Will stop flowing sooner, because it Will reach the applied voltage from the source. Overall less energy Will be stored. \$\endgroup\$
    – MaDrung
    Commented Aug 30, 2017 at 8:03
  • \$\begingroup\$ @Transistor Fixed that one. Will go through it again later. \$\endgroup\$
    – Joren Vaes
    Commented Aug 30, 2017 at 8:46

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