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Introduction to Matter, Energy and Electricity
A.
Bhatia
Overview
Have you ever wondered about
all the material or matter around us? What is it? Is there any universal
explanation for its appearance, properties, and behavior?
One theory that explained some
of the properties of matter was the molecular theory of matter, which states
that matter consists of small molecules in motion. This theory provides an
explanation of many characteristics of matter, including how heat works and why
materials change from solid to liquid to gas. This was followed by the atomic
theory of matter, which states that matter consists of atoms made of protons,
neutrons and electrons.
Matter is closely associated
with energy, which is defined as the ability to do work. What does this mean?
Work is done when matter is moved by applying a force--a push or pull. Lifting a
book off a table or throwing a baseball requires work. In science, something
must be moved to do work. Energy, therefore, is the capacity to move or effect
changes in matter.
Energy may take different forms like thermal energy, mechanical
energy, electrical energy or nuclear energy. Electricity is a form of energy
that comes from the movement of electrons in a closed circuit. This continuous
movement of free electrons through the conductors of a circuit is called a
current, and it is often referred to in terms of "flow," just like the flow
of a liquid through a hollow pipe. The force motivating electrons to "flow" in a
circuit is called voltage. Voltage is a specific measure of potential
energy that is always relative between two points. When we speak of a certain
amount of voltage being present in a circuit, we are referring to the
measurement of how much potential energy exists to move electrons from
one particular point in that circuit to another particular point. Without
reference to two particular points, the term "voltage" has no meaning.
Free electrons tend to move through conductors with some degree
of friction, or opposition to motion. This opposition to motion is more properly
called resistance. The amount of current in a circuit depends on the
amount of voltage available to motivate the electrons, and also the amount of
resistance in the circuit to oppose electron flow. Just like voltage, resistance
is a quantity relative between two points. For this reason, the quantities of
voltage and resistance are often stated as being "between" or "across" two
points in a circuit.
In this course, we will study
the basic
concepts and fundamentals behind electricity.
This 4-hr course material is based entirely on Naval Education and Training
Materials (NAVEDTRA 14173),
Electricity and Electronic Training Series;
Module-1 “Introduction to matter, energy and direct current” and covers
Chapter 1.
The student must take a multiple-choice quiz consisting of
twenty-five (25) questions at the end of
this course to obtain PDH credits.
Specific Knowledge or Skill Attained
This course teaches the following specific knowledge and
skills:
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State the meanings of matter, element, atom and energy
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Describe the relationship between matter, energy and
electricity
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List the differences between a conductor, an insulator, and a
semiconductor
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State the definition of static electricity and explain how it
is generated
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State the meanings of retentivity, reluctance, permeability and
ferromagnetism
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List the characteristics of magnetic lines of force (magnetic
flux)
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State how a difference of potential (a voltage or an
electromotive force) can exist.
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List six methods for producing a voltage (emf)
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State the meanings of electron current and indicate the
direction that an electric current flows.
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State the relationship of current to voltage.
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State the definitions of resistance and conductance
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Describe how the temperature, length and cross-sectional area
of a conductor affect its resistance and conductance values
Course
Click on the following PDF attachment and review the document
prior to taking
a quiz for credit.
Matter, Energy and Electricity (862 KB)
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