Part 1 (1/2)

Electricity for the 4-H Scientist

by Eric B Wilson

LESSON NO B-l

Credit Points 3

GETTING ACQUAINTED WITH ELECTRICITY

Electricity serves you best when you understand hoorks and use it properly As a 4-H member, you should know about electricity and help to show others the way to obtain its tre benefits as well as how to use it with safety

A good way to think of electricity is to compare it ater It acts a lot like water However it is made of tiny parts of atoms called electrons When there are , it is said to be negatively charged; when there is a shortage of electrons, it is positively charged As water flonhill, ”seeking it's level,” electrons flow froe

Electrical Conductors

Even if you're never going to repair a lamp or make a chick brooder, you should know about conductors and insulators This is because you happen to be a fairly good conductor of electricity Electricity will pass easily through you to other conductors--the ground, for instance When this happens you et a shock, burn, or serious injury But it doesn't ever have to happen, if you learn to understand your friend, electricity

Silver, copper, iron, aluood conductors Water, acids, and salts are too Electricity passes over or through theer the conductor, the more electricity it can carry When conductors are too s to et hot, melt, may start fires That's ire size is important

Electrical Insulators

Insulators are the opposite of conductors Electricity has trouble passing through solass are soood insulators It's the ah force, electricity can pass through just about anything--even ju the easiest paths It is always trying to get to the ground The earth attracts it It stays on the wires unless a person, a wet branch, or soround Do not touch any hichelectricity

Play It Safe

If you should touch a ”hot” wire accidentally and are standing on a dry piece of wood, the conducting pathway to the ground is not good and the electricityits wire But do not touch some other conductor with another part of your body This would coerous Always ood insulationwhichelectricity

Remember, too, insulation is of little use when it is wet Dew, e the whole picture If you understand electricity and how it acts, you'll be safe enough, because you won't take chances or expose yourself to injury

Electrical Ter Current_--Usually referred to as ”AC,” alternating current is current which reverses its direction of flow at regular intervals, 60 times a second

_Direct Current_--”DC” current flows only in one direction Battery current is DC

_Ampere_--Amperes are units by which the rate of flow of electrical current (electrons) isone point in a circuit, in one second This coallons per second

_Volts_--A volt is a unit to measure the tendency of electrons to e is the amount of ”push” behind the electrons It's like water pressure in a pipe Home power lines carry 115 volts (110 to 120 volts) For appliances such as electric stoves, washers and driers, a second 115-volt line should be added, giving 230 volts (220 to 240 volts)

_Watts_--Watts equal volts tiht bulbs, electric irons and other appliances are usually e they require and the number of watts

_Kilowatts_--Your electric bill usually reads in kilowatt hours A kilowatt is 1000 watts A kilowatt hour equals 1000 watts used for 1 hour One kilowatt equals about 1-1/3 horsepower A kilowatt is usually indicated by ”kw” and a kilowatt hour by ”kwh”