Series vs. parallel capacitors

In summary, the lab write-up refers to the experiment as "capacitors in parallel", but the results obtained suggest that the capacitors were actually connected in series. The DVM read 2.485V, which is not what was expected from a parallel circuit. It is suggested to check the capacitance and voltage in a series circuit to see if it matches the measured value.
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Homework Statement



I have some results of my lab here and I just want to check to make sure they make sense. The lab write-up refers to this part of the experiment as "capacitors in parallel" but I think they are actually in series (either that or we connected them incorrectly).

Here is a portion of the lab write-up:

For the formal experiment, begin with a pair of capacitors in parallel. Place a .1uF (the "u" should read as micro) mounted across the input of the voltage follower and mount a 1.0uF capacitor on a styrofoam block; connect the 2 capacitors to create a 1.1uF capacitor. Make sure that the 1.1uF is completely discharged. Charge a second 1.0uF capacitor to 5.0V and touch it to the uncharged 1.1uF capacitor. For safety, discharge the "charge-transfer" capacitor before putting it down. Compare the measured voltage to what is expected from a theoretical calculation.

Our DVM (which was attached to the voltage follower) read 2.485V.

I am confused because this part is labeled capacitors in parallel but it seems to me that when we touched the charged capacitor to the 1.1uF capacitor we made a series circuit, and that is why the voltage was not constant.

Does this seem right to anyone?


Homework Equations





The Attempt at a Solution

 
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  • #2
It says to connect the 1 and the .1 to make a 1.1 microfarad capacitance, so you should have connected them in parallel. That is, connect them together at one end and also at the other end.

However, in this case when you touch the 1 μf capacitor (1 nearly equal to 1.1) you ought to get about half of the 5 Volts on each rather than 2.485 V.
Perhaps you can work out what the capacitance and voltage are if they are in series and see if that works out to about the 2.4 V.
 

Related to Series vs. parallel capacitors

1. What is the difference between series and parallel capacitors?

In a series circuit, capacitors are connected one after the other, while in a parallel circuit, capacitors are connected side by side. This results in different overall capacitance and charge storage capabilities.

2. Which configuration is better for increasing capacitance?

Parallel capacitors are better for increasing capacitance as the total capacitance is equal to the sum of individual capacitances. In a series circuit, the total capacitance is less than the smallest individual capacitance.

3. How does the voltage affect capacitors in series and parallel?

In series capacitors, the voltage is divided among each capacitor according to their capacitance. In parallel capacitors, the voltage across each capacitor is the same.

4. What happens to the overall capacitance when adding capacitors in series and parallel?

When capacitors are added in series, the overall capacitance decreases. When added in parallel, the overall capacitance increases.

5. How does the capacitor arrangement affect the total charge stored?

In series capacitors, the total charge stored is the same for each capacitor. In parallel capacitors, the total charge stored is divided among each capacitor according to their capacitance.

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