Electricity: Electric Current

Electric current represents the flow of electric charge. It is usually carried by moving electrons in a conductor.
Current is measured in amperes (A).
Electric current can either be direct current (DC) or alternating current (AC). In DC, the electric charge always flows in one direction, while in AC, it changes direction periodically.
In a closed loop or circuit, the electric charge moves around continuously, enabling the transmission of electricity.
The amount of current depends on the voltage provided by the source (e.g., battery, generator) and the total resistance in the circuit.
Ohm’s law states that the current passing through a conductor between two points is directly proportional to the voltage across the two points, and inversely proportional to the resistance between them. It is given by the formula: I= V/R, where I is the current, V is the voltage, and R is the resistance.
Series circuits are circuits where components are connected end-to-end in a single path for current. In contrast, parallel circuits have more than one path for current to move through.
The total resistance in a series circuit is the sum of the resistances of each component.
Electric safety often depends on the proper management of current. Overloading circuits with excessive current can lead to fires due to the heating effect of current.
Electrical devices are often designed to function within a specific current range - flow of too much current (often due to low resistance or a short circuit) can lead to damage.
The role of a fuse or a circuit breaker in an electrical circuit is to prevent excessive current flow which could lead to overheating and possible fire.
To correctly read an ammeter, you need to ensure that it is connected in series with the component you intend to measure the current through.
Electrical energy is transferred through the movement of charges in the current. The rate at which this energy is transferred is power - measured in Watts (W).