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Hi.
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So this is a nice question because it requires us to study three different circuits, but they're both very simple.
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All of them are very similar because they are three oscillating alc circuits, so circuits that contains inductors and capacitors.
00:18
So let me try to sketch the circuits very quickly.
00:22
So one has an inductor and a capacitor.
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The other one has the same inductor, but it has two capacitors linked in parallel.
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We assume that the capacitors are identical.
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And the third circuit, which has the same inductor, and the same two capacitors, but this time linked in series.
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So let's call them a, b, and c.
00:48
We also know from the question that the frequency of these oscillating capacitors, so the frequency squared, is given by 1 over l, c, where l is the total inductance of the circuit and c is the total capacitance of the circuit.
01:04
And we have to order the three circuits or to rank them according to the time taken to fully discharge the capacitors during the oscillations.
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So we know that the capacitors will discharge in half a period or one period.
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So this means that the circuits which will discharge quicker are the circuits with a higher frequency.
01:26
So basically we have to order these three circuits in decreasing, in terms of their decreasing frequency.
01:38
So for the first circuit a, omega a squared will be simply given by 1 over lc.
01:45
If we assume that the inductor has an inductance l and the capacitor has a capacitor c...