Current, Resistance, and Ohm's Law

Electric Current

It is defined as the rate at which electric charge (q) flows through a cross-sectional surface of a conductor

Average Current

The _______ is formulated over a finite time interval

Instantaneous Current

The _________ refers to the limit of average current as time approaches zero (the derivative of charge with respect to time)

Ampere

The SI unit for Electric Current is Coulomb per second (C/s), universally known as the ________

Closed Circuit

An electric current can only flow continuously through a path that is entirely unbroken, known as a complete or ________

Open Circuit

An electric current can only flow continuously through a path that is entirely unbroken, known as a complete or closed circuit. The ________ breaks the path and halts current flow.

Conventional Current

The ________ is formally treated as the hypothetical movement of positive charges flowing from the positive terminal (+) toward the negative terminal (-).

Electron Current

__________ refers to the actual physical phenomenon in metals where negative electrons move in the opposite direction (from negative to positive), both producing identical electrical effects in a circuit.

Microscopic Conduction Model

The _________ indicates that electrons do not move smoothly in a straight line at a constant velocity inside a metal wire. Instead, they constantly interact, bounce, and collide with atoms and other free electrons, resulting in a complex, zig-zag path.

Electrical Movement

Materials possess intrinsic physical properties that dictate how easily they allow or restrict _________.

Electrical Conductivity

It refers to an intrinsic property measuring a material’s inherent capability to conduct or transmit electricity

Electrical Resistivity

It refers to an intrinsic property measuring how strongly a material opposes the flow of electric current, which is mathematically defined as the reciprocal of conductivity.

Conductors

This material is classified with extremely low resistivity and high conductivity

Silver, Copper, Gold

These elements/raw materials are classified with extremely low resistivity and high conductivity

Semiconductors

This material is classified with intermediate resistivity values

Pure Silicon, Germanium

These elements/raw materials are classified with intermediate resistivity values

Insulators

This material is classified with tremendously high resistivity values, which effectively block current

Glass, Amber, Lucite

These elements/raw materials are classified with tremendously high resistivity values, which effectively block current

Increases

The resistivity of metals and conductors ________ as temperature increases.

Crystal Lattice Structure

The reason behind the positive correlation between resistivity and temperature is because of the intense vibration of atoms in the ________, creating more structural obstacles that impede the motion of free electrons.

Decreases

The resistivity of semiconductors and carbon _________ as temperature increases because thermal energy frees more bound charge carriers for conduction.

Resistance

While resistivity (p) is a property of the material itself, _________ describes a specific physical component or object, which may take into account its shape and size.

Length

Resistance is directly proportional to __________

Cross-Sectional Area

Resistance is inversely proportional to __________

Ohm

The SI Unit for Electrical Resistance is Volt per Ampere (V/A), designated as the _______

Ceramic Core

Resistors are commonly constructed out of a carbon track wrapped around a ________

Semiconductive Metal Oxide Film

Resistors are commonly constructed out of a carbon track or made using a _________

Bands 1 & 2

There are a Standard Four-Band Color Code System, the ________ represents the first two significant digits of the value

Band 3

There are a Standard Four-Band Color Code System, the ________ acts as the multiplier (expressed as a power of 10)

Band 4

There are a Standard Four-Band Color Code System, the ________ specifies manufacturing precision/tolerance limit:

• No Band: ±20%

• Silver Band: ±10%

• Gold Band: ±5%

No Band

For Band 4 from the Standard Banding and Color Coding System of Resistors, the ±20% is represented by _________

Silver Band

For Band 4 from the Standard Banding and Color Coding System of Resistors, the ±10% is represented by _________

Gold Band

For Band 4 from the Standard Banding and Color Coding System of Resistors, the ±5% is represented by _________

Georg Simon Ohm

Who formulated Ohm’s Law in 1827?

Ohm’s Law

It describes the linear relationship between voltage and current

Current

V = IR is often called Ohm’s Law, but the true law states that the _______ is directly proportional to voltage since the resistance remains constant regardless of the applied voltage. Hence, this linear relationship is not universal.

Ohmic Materials

_________ satisfies I ∝ V, where they maintain a strict, steady linear relationship with constant slope on a current-vs-voltage plot across varying voltages.

Non-Ohmic Materials

________ do not display a linear proportional trend, where their resistance values shifts dynamically depending on the voltage applied or the current running through them.

Electric Power

It represents the rate at which electrical potential energy is converted or dissipated within a circuit component per unit time.

Derivation Path