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