Electric Current and Ohm's Law

Study Notes

Electric current is the flow of electrons through a conductor, such as a wire.
It is measured in amperes (A), where 1 A is 1 coulomb per second.
Current flow is typically denoted by the symbol I.
Electric current is a fundamental concept in electricity, and is essential for the operation of electrical devices and systems.

Ohm's Law states that the current flowing through a conductor is directly proportional to the voltage applied across it, and inversely proportional to the resistance of the conductor.
Mathematically, Ohm's Law is represented as: I = V/R, where I is the current, V is the voltage, and R is the resistance.
Ohm's Law is a linear relationship, meaning that if the voltage is doubled, the current will also double, provided the resistance remains constant.
Ohm's Law is a fundamental principle in electricity, and is widely used in the design and analysis of electrical circuits.

Series Circuits:
- A series circuit is a circuit where the components are connected one after the other, forming a single loop.
- The current flows through each component in sequence, and the total resistance of the circuit is the sum of the individual resistances.
- The voltage across each component is proportional to its resistance.
Parallel Circuits:
- A parallel circuit is a circuit where the components are connected between the same two points, forming separate branches.
- The voltage across each component is the same, and the total current is the sum of the individual currents.
- The total resistance of the circuit is less than the resistance of any individual component.

Kirchhoff's Laws are two fundamental principles in electricity, used to analyze electrical circuits.
Kirchhoff's Current Law (KCL):
- The sum of the currents entering a node in a circuit is equal to the sum of the currents leaving the node.
- Mathematically, this is represented as: ΣI_in = ΣI_out
Kirchhoff's Voltage Law (KVL):
- The sum of the voltage changes around a closed loop in a circuit is zero.
- Mathematically, this is represented as: ΣΔV = 0

Resistance is the opposition to the flow of electric current through a conductor.
It is measured in ohms (Ω), and is denoted by the symbol R.
Resistance depends on the material, length, and cross-sectional area of the conductor.
Resistance can be classified into three types:
- Linear Resistance: varies linearly with the voltage applied.
- Non-Linear Resistance: does not vary linearly with the voltage applied.
- Negative Resistance: decreases with an increase in voltage.

Electric current is the flow of electrons through a conductor, such as a wire.
It is measured in amperes (A), where 1 A is 1 coulomb per second.
Current flow is typically denoted by the symbol I.
Electric current is a fundamental concept in electricity, essential for the operation of electrical devices and systems.

Ohm's Law states that current is directly proportional to voltage and inversely proportional to resistance.
Mathematically, Ohm's Law is represented as: I = V/R, where I is the current, V is the voltage, and R is the resistance.
Ohm's Law is a linear relationship, meaning that if the voltage is doubled, the current will also double, provided the resistance remains constant.

Series Circuits:
- Components are connected one after the other, forming a single loop.
- The current flows through each component in sequence.
- The total resistance of the circuit is the sum of the individual resistances.
- The voltage across each component is proportional to its resistance.
Parallel Circuits:
- Components are connected between the same two points, forming separate branches.
- The voltage across each component is the same.
- The total current is the sum of the individual currents.
- The total resistance of the circuit is less than the resistance of any individual component.

Kirchhoff's Laws are fundamental principles in electricity, used to analyze electrical circuits.
Kirchhoff's Current Law (KCL):
- The sum of the currents entering a node in a circuit is equal to the sum of the currents leaving the node.
- Mathematically, this is represented as: ΣI_in = ΣI_out
Kirchhoff's Voltage Law (KVL):
- The sum of the voltage changes around a closed loop in a circuit is zero.
- Mathematically, this is represented as: ΣΔV = 0

Resistance is the opposition to the flow of electric current through a conductor.
It is measured in ohms (Ω), and is denoted by the symbol R.
Resistance depends on the material, length, and cross-sectional area of the conductor.
Resistance can be classified into three types:
- Linear Resistance: varies linearly with the voltage applied.
- Non-Linear Resistance: does not vary linearly with the voltage applied.
- Negative Resistance: decreases with an increase in voltage.