Electric current

Manual electric current strength.

Electric Current and Electrical Voltage.

Voltage and current (current) are quantitative fundamental concepts about which it is necessary to have a clear understanding of each person related to the field of activity with electricity (electrician, electronics engineer, radio technician, etc.).

Current strength (or simply current): conditionally, the current strength is denoted by the letter “I”. An electric current is the amount of electric charge (in solids, electrons) passing through a cross section of a conductor per unit time. The unit of measurement of electric current is amperes (in honor of the scientist who discovered this phenomenon). As a rule, in electrics, the current is measured in amperes.

Voltage (or potential difference): conventionally, the voltage is indicated by the letter “U”, in some cases “E”. The potential difference (electrical voltage) between two points is the work (or energy) that is spent on making the movement of a single positive electric charge from a point with a lower potential to a point with a greater potential (that is, the first point has a more negative electric potential compared to second point). In other words, it is the energy that is released when a single electrical charge “rolls” from a high electric potential to a low potential. Voltage is also called electromotive force EMF

Current measurement circuit with ammeter

According to the law, the current through the wires flows at any point in the closed circuit of the same magnitude. Therefore, in order to measure the amount of current, you need to connect the device, breaking the circuit in any convenient place. It should be noted that when measuring the magnitude of the current does not matter what voltage is applied to the electrical circuit.