I have a question about capacitors. I have heard that capacitors can be used for "smoothing out the voltage". How would this work? Once the capacitor is charged wouldn't electricity just stop flowing through it?
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I have a question about capacitors. I have heard that capacitors can be used for "smoothing out the voltage". How would this work? Once the capacitor is charged wouldn't electricity just stop flowing through it?
If you were putting perfectly stable dc voltage to it, then yes (but electric doesn't flow "through it"). If that were the case, you wouldn't need the cap anyhow.
After the capacitor charges, if the dc voltage starts to drop, it becomes more negative than the plate of the capacitor. The capacitor would then start to discharge back into the circuit to try to maintain the voltage level, effectively smoothing it.
The capacitor would have to be chosen by the frequency of the change and the amount of change. Too small and it won't be able to smooth out the voltage. Too big takes too long to charge and isn't responsive enough to the changes.
Think of a capacitor along the lines of a gyroscope - it tends to resist change in the voltage.
I have a question about capacitors. I have heard that capacitors can be used for "smoothing out the voltage". How would this work? Once the capacitor is charged wouldn't electricity just stop flowing through it?
Capacitors "resist changes in voltage". Once they are charged, no current flows unless something changes. (ignoring leakage current).
In parallel with the voltage or signal, they can smooth or filter the voltage (a low-pass filter).
In series with the voltage or signal, they "block DC" and pass changes or high frequencies (a high-pass filter).