This article will explain what electric current is and how to divide it into different categories.
What is the definition of electric current?
In electromagnetism, we call the flow of electricity through a conductor in a certain amount of time current intensity. Its abbreviation is: Electric current, the current symbol is I, the unit is Ampere (A), referred to as "A".
Free charges in a conductor move in a certain direction because of the electric field, making an electric current.
Electricity stipulates that the direction in which positive charges flow is the direction of current. In addition, engineers also consider the directional flow direction of positive charges as the direction of current in engineering.
Current intensity measures how much charge flows through a conductor in a set time, indicating the strength of the current.
Nature has many types of charge carriers.
For example: movable electrons in conductors, ions in electrolytes, electrons and ions in plasma, and quarks in hadrons. The movement of these carriers creates an electric current.
What are the ways to categorize current?
Electric current divides into alternating current and direct current.
What precisely does alternating current mean?
This refers to periodic changes in both the magnitude and direction of the current. Wall-plugged appliances in daily life use civilian AC power. People widely use alternating current in family life and industrial production. The domestic voltage of 220V and the general industrial voltage of 380V are both dangerous voltages.
What exactly is direct current?
This means that the direction of the current does not change over time. The removable external power supplies used in daily life provide direct current.
People commonly use direct current in small devices like flashlights and mobile phones for power.
DC power supplies include dry batteries (1.5V), lithium batteries, storage batteries, etc. Because the voltage of these power supplies will not exceed 24V, they are safe power supplies.
The above is an introduction to current and current classification.
