Download SOL_Study_Book_4.3_Electricty

SOL Study Book
Fourth Grade
Electricity
Table of Contents
Page 1: Electricity and Circuits
Page 2: Insulators and Conductors
Page 3: Static Electricity
Page 4: Magnetism
Page 5: Important People
Electricity and Circuits
Electric current is created by a continuous flow of negative
charges (electrons).
A circuit is the pathway taken by an electric current.
The 2 types of basic circuits are open and closed.
A closed circuit allows the movement of electrical energy.
An n open circuit doe NOT allow the electric current to
flow.
The 2 types of closed circuits are parallel and series.
In a parallel circuit, there are two or more pathways for
electric current to flow. If one pathway is opened, the other
one still works.
In a series circuit, there is only one pathway for electricity.
If it is open the flow of current stops.
Electricity can be changed into heat, light or mechanical
energy.
Page 1
Insulators and Conductors
Conductors are materials that electrical energy moves
through easily. Metals and water are some examples of
conductors.
In conductors, energy (electric current) passes more or less
easily because of the material’s resistance.
Materials with a greater resistance will not allow energy to
flow quickly. In materials with low resistance, energy
flows easily.
Insulators are materials that do NOT allow electric current
to pass easily. Some examples of insulators are rubber,
plastic, and wood.
Page 2
Static Electricity
All matter is made up of tiny particles called atoms.
Each atom contains 3 basic parts:
protons = positive charge (+)
electrons = negative charge (-)
neutrons = no charge (neutral)
Protons and neutrons are in the nucleus or center core of the
atom. Electrons orbit around the nucleus.
Most objects have the same number of electrons and
protons, so they are electrically balanced.
Sometimes objects gain or lose electrons through friction
(rubbing of 2 objects together). This causes an object to
gain or lose electrons, making it electrically charged.
Objects that gain electrons will become negatively charged.
Objects that gain protons will become positively charged.
Two objects with like charges (+ and + - or -) will repel,
or push away from each other. Objects with opposite
charges (+ and -) will attract to each other.
Lightning is the discharge of static electricity in the
atmosphere.
Page 3
Magnetism
Metals that contain iron will attract other such metals.
Nickel and cobalt will also attract other metals.
The magnetic field is the area around the poles of a magnet
that extends out in an arched pattern where magnetic force
is strong.
An electric current can create a magnetic field. A current
flowing through a wire creates a magnetic field. Wrapping
a wire around certain metals and making a closed circuit is
an example of an electromagnet.
Electromagnets are very strong. They can also be turned
off and on by controlling the flow of electricity.
A moving magnetic field can also create electricity.
Page 4
Important People
Benjamin Franklin discovered that lightning is a form of electricity found
in nature.
Thomas Edison invented the light bulb.
Michael Faraday discovered that by moving a magnet near a wire,
electricity could be made. He also did experiments with electromagnets.
Page 5