ELECTRO - LESSON 1 TO 3

Vocabulary-style flashcards covering key definitions, units, laws, and electrical components from Lessons 1 and 2 of Physics of Electricity.

Proton

A subatomic particle located in the nucleus that carries a positive electrical charge.

Electron

A subatomic particle carrying a negative electrical charge that can be gained or lost by an atom.

Neutral Atom

An atom containing equal numbers of protons and electrons.

Cation

A positively charged ion formed when an neutral atom loses electrons.

Anion

A negatively charged ion formed when an atom gains electrons.

Anode

The positive electrode, universally color-coded red, which attracts negatively charged anions.

Cathode

The negative electrode, universally color-coded black, which attracts positively charged cations.

Conductor

A material (such as copper) with loosely held outer-shell electrons that readily transmits electrical charges.

Insulator

A material (such as rubber) with firmly held outer-shell electrons that does not readily transmit electrical charges.

Volt

The standard unit of electrical potential.

Coulomb

The standard unit of quantity of electricity.

Farad

The standard unit of electrical capacitance.

Electromotive Force (EMF)

The force that produces the movement of electrons from negative to positive due to a potential difference.

Ampere

The unit of electrical current, equal to $1\text{ C/sec}$.

Ohm's Law

The physical law stating that current varies directly with electromotive force (EMF) and inversely with resistance, defined by the formula $I = \frac{E}{R}$.

Ohm

The standard unit of electrical resistance.

Series Circuit Resistance

The total resistance in a series circuit, calculated as the sum of all individual resistances.

Parallel Circuit Resistance

The total resistance in a parallel circuit, which is always less than any individual resistance in that circuit.

Joule's Law

The physical law stating that electrical energy is converted into thermal energy as current passes through a conductor, defined by the formula $Q = I^2RT$.

Electrical Power

The rate of doing work in an electrical system, defined by the formula $P = \text{EMF} \times I$.

Transformer

An electrical device, also known as an auto voltage regulator, that operates primarily through electromagnetic induction.

Primary Coil

The coil in a transformer where current from the electrical source initially flows.

Secondary Coil

The coil in a transformer that receives an induced electromotive force through electromagnetic induction.

Even-Ratio Transformer

A transformer with an equal number of turns in the primary and secondary coils, whose main function is to render the current earth-free.

Step-Down Transformer

A transformer whose secondary coil has fewer turns than the primary coil, causing the secondary voltage to decrease.

Step-Up Transformer

A transformer whose secondary coil has more turns than the primary coil, causing the secondary voltage to increase.

Static Transformer

A transformer that produces a fixed output voltage.

Variable Transformer

A transformer with a movable contact that allows the operator to select or change the voltage output.

Autotransformer

A transformer consisting of a single coil equipped with four contact points.

Fuse

An electrical safety component connected in series, made of a low melting point material, acting as the weakest point in a circuit to open the circuit when excessive current flows.