What are voltage, current, and resistance? How are they related?
1 Answer
Voltage, current, and resistance are fundamental concepts in the field of electrical and electronic engineering. They are interrelated and play a crucial role in understanding and analyzing electrical circuits.
Voltage:
Voltage, also known as electric potential difference or electric potential, is the measure of the electric potential energy per unit charge between two points in an electrical circuit. It's often represented by the symbol "V" and is measured in volts (V). Voltage represents the driving force that pushes electric charges through a circuit. In simpler terms, it's the "pressure" that causes electric charges to flow from one point to another.
Current:
Current refers to the flow of electric charges (usually electrons) through a conductor. It is the rate of flow of charges and is measured in amperes (A). Current is represented by the symbol "I." Electric current can be thought of as the "amount" of charge passing through a point in the circuit per unit of time. Current flows in response to a voltage difference, moving from higher voltage points to lower voltage points.
Resistance:
Resistance is the opposition that a material offers to the flow of electric current. It's caused by collisions between electrons and atoms within the material. Resistance is measured in ohms (Ω) and is represented by the symbol "R." The relationship between voltage, current, and resistance is described by Ohm's Law.
Ohm's Law states that the current (I) flowing through a conductor between two points is directly proportional to the voltage (V) across the two points and inversely proportional to the resistance (R) between them:
=
I=
R
V
In other words:
If the voltage across a circuit increases while the resistance remains constant, the current will increase.
If the resistance increases while the voltage remains constant, the current will decrease.
This relationship helps in understanding how changes in voltage and resistance affect the current flowing through a circuit.
In summary, voltage provides the driving force for current to flow, and resistance restricts the flow of current. Ohm's Law establishes the mathematical relationship between these three fundamental concepts in electrical circuits.
Voltage:
Voltage, also known as electric potential difference or electric potential, is the measure of the electric potential energy per unit charge between two points in an electrical circuit. It's often represented by the symbol "V" and is measured in volts (V). Voltage represents the driving force that pushes electric charges through a circuit. In simpler terms, it's the "pressure" that causes electric charges to flow from one point to another.
Current:
Current refers to the flow of electric charges (usually electrons) through a conductor. It is the rate of flow of charges and is measured in amperes (A). Current is represented by the symbol "I." Electric current can be thought of as the "amount" of charge passing through a point in the circuit per unit of time. Current flows in response to a voltage difference, moving from higher voltage points to lower voltage points.
Resistance:
Resistance is the opposition that a material offers to the flow of electric current. It's caused by collisions between electrons and atoms within the material. Resistance is measured in ohms (Ω) and is represented by the symbol "R." The relationship between voltage, current, and resistance is described by Ohm's Law.
Ohm's Law states that the current (I) flowing through a conductor between two points is directly proportional to the voltage (V) across the two points and inversely proportional to the resistance (R) between them:
=
I=
R
V
In other words:
If the voltage across a circuit increases while the resistance remains constant, the current will increase.
If the resistance increases while the voltage remains constant, the current will decrease.
This relationship helps in understanding how changes in voltage and resistance affect the current flowing through a circuit.
In summary, voltage provides the driving force for current to flow, and resistance restricts the flow of current. Ohm's Law establishes the mathematical relationship between these three fundamental concepts in electrical circuits.