Electrical Principles Hard Vocab

Static Electricity

A build up of electric charge on the surface of an object. It stays in one place, and doesn’t flow like current electricity.

• Usually caused by friction (rubbing two objects together).

• Electrons move from one object to another.

  Ex: Rubbing a balloon on your hair → the balloon becomes negatively charged, your hair becomes positively charged → your hair stands up.

DC Current

Electric current that flows in one direction only.

Source: Batteries

Ex:A flashlight uses DC current from a battery to light the bulb.

AC Current

Definition:
Electric current that reverses direction many times per second.

Source:

• Wall outlets / power plants

Example:
The electricity that powers your home is AC — it flows back and forth rapidly.

Motor

Definition:
A device that converts electrical energy into mechanical energy (motion).

How it works:

• A current flows through a coil inside a magnetic field, causing it to spin.

Example:
Electric fans, toy cars, washing machines.

Generator

Definition:
A device that converts mechanical energy into electrical energy.

How it works:

• A coil rotates inside a magnetic field to produce electricity.

Example:
Power plants use generators to supply electricity to homes and schools.

Ammeter

Definition:
A device that measures electric current in a circuit (in amperes).

Example:
Used to check how much current flows through a wire

Short Circuit

Definition:
A fault in a circuit where current takes an unintended path with little or no resistance.

Danger:
Can cause overheating, sparks, or fires.

Example:
Exposed wires touching each other can create a short circuit.

Insulators

Definition:
Materials that do NOT let electricity flow easily.

Examples:
Rubber, plastic, glass.

Use:
Used to protect us from electric shock.

Fuse

Definition:
A safety device that melts and breaks the circuit if too much current flows.

Example:
Prevents fires in electronics when there's a power surge.

Ground Wire

Definition:
A wire that directs excess electricity safely into the ground to prevent electric shocks.

Use:
Part of three-prong plugs and household wiring.

Electrochemical Cell

Definition:
A device that produces electricity using chemical reactions.

Parts:

• 2 electrodes (metals)

• 1 electrolyte (liquid or paste)

Dry Cell

Definition:
A type of electrochemical cell with a paste electrolyte.

Example:
AA or AAA batteries in remotes and flashlights.

Wet Cell

Definition:
An electrochemical cell with a liquid electrolyte.

Example:
Car batteries use wet cells filled with acid.

Variable Resistor

Definition:
A resistor that can change its resistance to control the amount of current in a circuit.

Example:
Used in light dimmer switches or volume knobs.

Microcircuits

Definition:
Tiny electronic circuits made up of miniature components, often found on microchips.

Use:
Found in computers, phones, and other small electronics.

Transformers

Devices that change the voltage of AC electricity — either increase (step-up) or decrease (step-down) it.

Example:
Used in power lines to safely deliver electricity to homes

Potential Gravitational Energy

Definition:
Stored energy an object has because of its height above the ground.

Example:
A rock on a cliff or water behind a dam.

Electromagnetic Induction

Definition:
The process of creating electricity by moving a conductor through a magnetic field.

Use:
How generators make electricity!

Power Grid

Definition:
A network that carries electricity from power plants to homes and businesses.

Includes:
Power lines, transformers, substations, etc.