Elektrivoolu

Elektrivoolu refers to the flow of electric charge, typically electrons, through a conductive material. This movement of charge is driven by a potential difference, also known as voltage, which creates an electric field. The strength of the electric field dictates how quickly the charges move. The SI unit for electric current is the ampere (A), named after André-Marie Ampère. One ampere is defined as one coulomb of charge passing a point in one second.

There are two main types of electric current: direct current (DC) and alternating current (AC). In DC, the charge flows in one direction consistently. Batteries and solar cells produce direct current. In AC, the direction of the charge flow periodically reverses. This is the type of electricity that is supplied to homes and businesses through the power grid. The frequency of this reversal is measured in hertz (Hz), with 50 Hz and 60 Hz being common in different parts of the world.

The relationship between voltage (V), current (I), and resistance (R) in a circuit is described by Ohm's Law, which states that V = I * R. Resistance is a measure of how difficult it is for electric current to flow through a material. Conductors, like copper and aluminum, have low resistance, allowing current to flow easily, while insulators, such as rubber and glass, have very high resistance and impede the flow of current. Understanding elektrivoolu is fundamental to the study and application of electricity in various technologies and everyday devices.