Electric current is the flow of electric charge through a conductor, such as a wire. It is one of the fundamental concepts in electricity and is measured in units called amperes (A). Electric current is essential for the functioning of various electrical and electronic devices, as well as for the distribution of electrical power.
There are two types of electric current:
Direct Current (DC): In a direct current, the flow of electric charge is continuous and always in one direction. Batteries and most electronic devices produce direct current. The symbol for direct current is "DC."
Alternating Current (AC): Alternating current reverses its direction periodically. This means that the electric charge changes its flow direction back and forth over time. AC is what is commonly used for the distribution of electricity in power grids and is the type of current that comes out of electrical outlets in most homes and buildings. The symbol for alternating current is "AC."
The flow of electric current is driven by voltage. Voltage, also known as electric potential difference, is the force that pushes electric charges through a conductor. It is measured in volts (V). In simple terms, voltage is what causes electrons to move from one point to another.
Ohm's Law is a fundamental principle that relates the current, voltage, and resistance in an electric circuit:
Ohm's Law:
=
I=
R
V
Where:
I is the current in amperes (A).
V is the voltage in volts (V).
R is the resistance in ohms (Ω).
Resistance is the opposition that a material offers to the flow of electric current. Materials with higher resistance impede the flow of current more than materials with lower resistance. Resistance is influenced by factors such as the material's composition, length, cross-sectional area, and temperature. The unit of resistance is the ohm (Ω).
In summary, electric current is the movement of electric charge through a conductor, and it is crucial for various electrical devices and systems. It can be either direct current (DC), which flows in one direction, or alternating current (AC), which changes direction periodically. Current is driven by voltage, and Ohm's Law describes the relationship between current, voltage, and resistance in an electric circuit.