What's the function of electric energy meter installation in the first home circuit Isn't it true that if you install it in the back and use electricity in the front, it won't work That is to say, the watt hour meter will not reverse as the ammeter

What's the function of electric energy meter installation in the first home circuit Isn't it true that if you install it in the back and use electricity in the front, it won't work That is to say, the watt hour meter will not reverse as the ammeter

The physical meaning of current
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The amount of electricity per unit time passing through the cross section of a conductor

Electromagnetics: the physical meaning of current element
Why should we introduce the concept of current element in electromagnetics? What does "element" mean? High school textbooks say that the timing of current element is for a very short wire, why should it be very short?
That is to say, the length of the current element is infinitely close to zero?

First of all, the current element refers to the product of the current I and the differential DL of the wire, that is, I * DL refers to the current element. Here, DL is an infinitesimal quantity, and this concept will be explained in depth after going to university. Secondly, the current element is introduced to better understand the electromagnetic phenomenon. Generally, the object of study is often irregular, and

The physical meaning of circuit negative resistance

In electronic circuits, static resistance is the ratio of voltage across circuit elements and power flow through it. However, the ratio of voltage to power flow may vary with voltage or power flow

How to define the direction of current?

Physics stipulates that the direction of current is the direction of positive charge moving