Electrical Energy Fundamentals Part 2

Step-down transformer

A transformer that steps down, or decreases, the voltage exiting the transformer

Step-up transformer

A transformer that steps up, or increases, the voltage exiting the transformer

Kilowatt-hours (kWh)

A unit of electrical power. One kilowatt-hour is the equivalent of 1000 joule.

Branch

One of the pathways in a parallel circuit

Watt's law

The law that states that relationship between power, voltage, and current

Power

The rate of doing work. Electric __ is measured in watts or volt-amperes

Watts

The unit of measurement used in expressing power delivered to or consumed by an electrical device. Named after James Watt

Olms

The units of measurement used to express resistance, Named after George Simon Ohm

series circuit

a circuit having a single path for current flow

parallel circuit

a circuit with multiple paths available for current flow

substation

a collection of transformers that changes the voltage of the electrical power and redistributes it along another set of conductors

Complex circuit

a combination of a series and parallel circuit

transformer

a device that transfers electrical energy from one circuit to another, usually at a different voltage through electromagnetic induction

Left-hand rule

a rule for determining the direction of flow in a conductor caused by electromagnetic induction. Also known as Fleming's rule

joules

a unit of electrical power. One joule equals one watt-second. Named after Prescott Joule.

load

device that converts electricity into another form of energy

energy

the ability to do work

windings

the coils of wire in an electrical device. ___ are used in generators, motors, and transformers

Ohm's law

the law that states the relationship between voltage, resistance, and current

resistance

the opposition to the flow of electrons through a conducter

circuit

the pathway over which electrons can move

Work

the process of changing energy from one form to another, or causing an object to gain or lose energy

electromagnetic induction

the process of producing an electromotive force by varying the magnetic field surrounding a conducter

secondary winding

the transformer winding connected to the load

Primary winding

the winding of a transformer that creates a magnetic field and is connected to the power source side

Volt-amperes

volts multiplied by amps. The amount of power an electric system can provide or the amount of power an electrical device required. equivalent to watts in simple sytems