2017年1月2日星期一

The Confusing Direction of Current

 epcb

The direction of the current is a bit confusing. Does the current flow from the positive to the negative terminal of a circuit, or the other way around? Actually, it doesn’t matter. When you need to do calculations, all you need to do is to decide on a direction and make your calculations based on that direction. No matter which direction you chose, the results will be the same.

But what is right? No direction is the absolutely “right” direction. Current can flow both ways, depending on if there are positive or negative charge carriers at work. In metals, we have negative charge carriers, also called electrons. They flow from negative to positive. So, in a normal electric circuit based on metal, electrons will flow from the negative terminal to the positive. But, the conventional way of talking about current direction is from positive to negative.  

没有评论:

发表评论