Electricity, Electrical Systems & Related Technologies Lecture

Fill-in-the-blank flashcards covering definitions, units, components, wiring methods, protection devices, instruments, communication and control systems referenced throughout the lecture notes.

___ is a form of energy generated by friction, induction, or chemical change and involves the motion of free electrons through a conductor.

Electricity

An _ is a network of electrical components deployed to supply, transfer, and use electric power.

electrical system

Electricity is called a __ energy source because it is produced by converting primary sources like coal, solar, or wind.

secondary

The conversion of sunlight directly into electricity using semiconductor devices is called .

photovoltaics (PV)

A solar technology that uses mirrors or lenses to focus sunlight into a small beam is known as solar power.

concentrated

Electricity generated from nuclear reactions that produce heat for steam turbines is called __ power.

nuclear

Harnessing moving water to produce electricity is known as __ power.

hydroelectric

Electricity produced by turbines turned by air movement is called _ energy.

wind

Using the Earth's internal heat to generate electricity refers to __ power.

geothermal

An electric current that reverses direction periodically is called __ current.

alternating (AC)

An electric current flowing in only one direction is called __ current.

direct (DC)

The unit of electric current is the __, equal to one coulomb per second.

ampere

Battery capacity is often measured in __-hours.

ampere

The device that stores electric charge using separated conductors is a __.

capacitor

A closed path in which electrons flow is an electric __.

circuit

An automatic device that stops current flow when it exceeds a preset level is a __ breaker.

circuit

Materials like copper or aluminum that allow current to flow easily are called __.

conductors

The flow of electric charge through a conductor is called __.

current

__ strength is the maximum electric field a material can withstand without breakdown.

Dielectric

The number of cycles per second of an AC signal is its __, measured in hertz.

frequency

A protective device containing a metal strip that melts under excess current is a .

fuse

A machine that converts mechanical energy to electrical energy is a __.

generator

A reference point or direct physical connection to the Earth in a circuit is called __.

ground

A safety device that quickly de-energizes a circuit when ground current rises is a __ (acronym).

GFCI (Ground Fault Circuit Interrupter)

The unit of inductance that equals one volt induced per ampere-per-second change is the __.

henry

A device that converts DC to AC is an __.

inverter

Electrical energy consumption is billed in __-hours.

kilowatt

One kilowatt equals __ watts.

1000

Anything that consumes electrical energy, such as lights or motors, is called a __.

load

The sudden loss of load causing generator over-frequency is termed load __.

rejection

The unit of electrical resistance is the __.

ohm

An instrument that measures resistance is an __ meter.

ohm

A circuit with multiple paths for current flow is a __ circuit.

parallel

A circuit with only one path for current is a __ circuit.

series

Opposition to current flow is called __.

resistance

A device made of wire or carbon that provides specific resistance is a __.

resistor

The rotating part of a motor or generator is the __.

rotor

A substance whose conductivity lies between conductors and insulators is a __.

semiconductor

A fault where conductors touch and divert current from its intended path is a __ circuit.

short

A three-lead semiconductor device capable of amplification is a __.

transistor

Apparent power is measured in __-amperes.

volt

The electrical "pressure" that drives current is called __.

voltage

One watt equals one __ per second.

joule

According to Ohm’s Law, I = _ / R.

V

In Ohm’s Law, V = __ × R.

I

Copper is widely used as a conductor because of its high __ and thermal conductivity.

electrical

THHN wire stands for Thermoplastic High Heat-resistant __-coated wire.

Nylon

In __ conduit wiring, pipes are hidden inside walls and covered with plaster.

concealed

__ wiring uses PVC-insulated cables fastened directly on cleats for temporary setups.

Cleat

Raceways protect cables from heat, humidity, water, corrosion, and other __ threats.

physical

Electromechanical devices that control circuits by foot pressure are called __ switches.

foot

A switch sensing liquid levels in tanks is a __ switch.

level

Overcurrent protective devices include fuses, circuit breakers, and __ (acronym).

GFCI

An enclosure that houses electrical connections outdoors is a __ box.

junction

An instrument used to measure current in a circuit branch is an __.

ammeter

A meter that clamps around a conductor to read current is a __ meter.

clamp

A device converting sound energy into electrical signals at a transmitter is an __ transducer.

input

A stand-alone voice communication system within a building is called an __ system.

intercom

A privately owned telephone switch network within an organization is abbreviated __.

PBX (or PABX)

A __ displays images from computers or other devices onto a screen.

projector

Large, seamless display assemblies made of many LED panels are termed video __.

walls

A PA system increases the apparent __ of a voice or music source.

volume

An intelligent network connecting HVAC, lighting, and security on one platform is a __ Automation System (BAS).

Building

In BAS, devices that monitor temperature, humidity, or occupancy are called __.

sensors

In robotics, the interdisciplinary field dedicated to designing and using mechanical robots is simply called __.

robotics