# Telling if Capacitors are in Parallel or Series So C1 and C2 are in series. But if each one is placed in red boxes, they are in parallel?

It's confusing going jumping between current, capacitors, and resistance.

For me it's kinda confusing deciding which one is in parallel and which one is in series.

## 6 Answers

There are no dumb questions, just bad teachers.

In your case, both capacitos are in series. IT doesn't matter if they are upside or in the red boxes, it's series.

How can you tell? This is a rule of thumb: you have to check if there is more than one possible path.

• Two elements are in series if they are one after another. There is only one path, so, if you follow the wire, you will find the first element and then the second element. No matter how far they are, if there is only one way, you cannot avoid any element, they are in series. It's like a road. If the road goes through two villages, and there is only one road, it is series.

• On the other hand, two elements are in parallel when each element is in a different branch of the circuit. This implies that there must be a bifurcation. In the road analogy, you'd need to have one village on the left path and another on the right path. (This can be generalized to whatever number of branches).

The only caution is: do not mix them. If there's one element and then the bifurcation, that's nothing. The bifurcation must be BEFORE the elements, so that each element is already in a branch. Thsi is different than an element on the main way and then a bifurcation, that's nothing.

So, in your circuit, there is only one path. No bifurcation at all, so there's no doubt it is series.

• thank you so much – jee Jun 8 at 20:34
• @jee If this answer helped, make sure to mark it as the best answer for others to see :) – F16Falcon Jun 9 at 2:35

it may be easier to understand the concepts of series and parallel by considering the batteries in a flashlight. They are usually on top of each other, + to -, this is in series and will deliver the voltage of both added together, usually 1.5 + 1.5 = 3 volts to the bulb. If the batteries were laying beside each other with a wire connecting - to - then to the bulb, and another wire connecting + to + then to the bulb, then the batteries are in parallel and the bulb will get the same voltage as each battery, usually 1.5 volts, but the amperage will add up. batteries in series the voltage adds batteries in parallel the amperage adds

For circuit components consisting of two terminals, in order for them to be considered connected in parallel, one terminal of the first component must be connected to one terminal of the second component. The second terminal of the first component must be connected to the other terminal of the second component. In your circuit, one terminal of each capacitor is connected to the battery, and not to the other terminal, so they can not be considered in parallel.

Two components are considered connected in series when all the current that goes to one of the components has to also go to the other component. There can not be any alternative paths. In your circuit current all of the current going to one the capacitors must also go to the other. Therefore they are in series.

Hope this helps.

If two (two-terminal) circuit elements are series connected, they have identical (not just equal) current through. It's easy to see that the two capacitors in your circuit are series connected since all of the current through C1 is through C2, i.e., they have identical current through (one ammeter measures the current through both capacitors). This is true regardless of whether they are drawn in the red boxes or along the top path.

If two circuit elements are parallel connected, they have identical (not just equal) voltage across. It's easy to see that the two capacitors in your circuit are not parallel connected since a voltmeter connected across C1 measures the voltage across C1 but not the voltage across C2, i.e., the capacitors do not have identical voltage across (though they will have equal voltage across when C1 = C2).

For understanding how to find whether capacitor are in series or in parallel .answer to your question whether they are placed in red boxes still they are in series .CONDITION FOR capacitor in series that current across them should be same and for parallel if the two capacitor are in parallel their each end should joint with each other it mean positive end of capacitor 1 should be connect to positive end of capacitor 2 and same with negative end

I think of them as a single physical object:

If I have a 100 ohm resistor and imaginarily cut it in the middle so it is now two 50 ohm resistors: they are in series (mind you, it's not really cut, I just decided to call it 2 resistors), then it simply must be 100 ohms. So series resistors add linearly.

With a single 100 farad capacitor (2 plates), I now declare a left side and a right side, each 50 farad, in parallel. They must add to 100 farad, so parallel capacitors add in linearly.

Thus, parallel resistors (series capacitors) add harmonically.

This also works with springs and decay rates.