Capacitors
1. What's the Buzz About Capacitor Current?
Alright, let's tackle this capacitor conundrum head-on. The question of whether capacitors "flow from positive to negative" is a bit like asking if a battery drains from positive to negative. It's partially true, but there's a crucial nuance that changes everything. Think of it less like a straightforward river of electrons and more like a very polite electronic dance. It's not a continuous flow, but a shift of charge.
The keyword here is "current." We often talk about current flowing in a circuit, and conventionally, we depict it as moving from positive to negative. This is a historical convention, and its important to remember that current actually consists of electrons moving. Since electrons have a negative charge, they technically move from negative to positive. But the established convention is still in play!
Now, a capacitor doesn't allow direct, sustained current flow through it like a wire would. Instead, it stores charge. When a voltage is applied, electrons are pulled away from one plate of the capacitor (making it positively charged) and pushed onto the other plate (making it negatively charged). This separation of charge is what creates the capacitor's electric field and its ability to store energy. So, it's less about flow and more about a buildup or depletion on each plate.
It's like a tiny rechargeable battery. Think of it like filling a bucket with water. You're not continuously running a stream through the bucket, but you are adding water to one side and taking it away from the other. When you "discharge" the capacitor, that stored charge (electrons) moves to balance the potential difference, creating a brief current in the circuit. The direction, according to conventional current flow, would appear as if it's going from the positive to the negative plate. But, physically, the electrons are doing the opposite!
