# Tag Info

1 vote

### Thought experiment: EM fields and coils

You've designed an air-core transformer. Depending on the direction of the windings relative to each other, this could (assuming an equal number of turns in the two windings) either Effectively null ...
• 27.6k
1 vote

### Maximum Impedance for LCR series circuit

The answer is very simple. The total complex impedance Z is $$Z = R + jšL + 1/(jšC)$$ where $R$ is the ohmic resistance, $j$ is the imaginary unit, $š$ is the angular frequency, $L$ is the ...
• 16.1k

### Maximum Impedance for LCR series circuit

The "conditions" are circuit dependent. Sometimes there may not even be a maximum (such as a single capacitor, whose impedance goes to infinity as frequency goes to zero). The most common ...
• 49.1k

### Which of these is the right way to interpret finding the current across a coil

Model the coil as an ideal inductor in series with its 100 ohm resistance. That, in turn, is in series with the 50 ohm resistor. The voltage across the inductor is across the combination of the ideal ...
• 71.9k
The current does periodically become zero in an $LC$ circuit. However, since the current obeys a sinusoidal oscillation with respect to time, its time-derivative would be a cosinusoidal function - i.e....
Plotted below are three graphs of $y$ against time, $t$. Everything the blue graph does the orange graph has done earlier in time. In this case we can say that the blue graph lags the orange graph by ...