Download Electricity Unit Notes: pp

Name: _________________
Period: _________________
Date: __________________
Electricity Unit Notes: pp. 6 – 19
1) Main Entry: elec·tric·i·ty
Function: noun
”a fundamental entity of nature consisting of negative and positive kinds,
observable in the attractions and repulsions of bodies electrified by friction and in
natural phenomena (as lightning or the aurora borealis), and usually utilized in
the form of electric currents”
a) Positive and Negative Charge
i) Atoms are ________ as there are equal numbers of protons and electrons.
ii) Ions, _______ and ________, are electrically charged as they have either
extra or fewer electrons as compared to their number of protons.
iii)
iv) ___________- An imbalance of electric charge due to rubbing two objects
together causing the removal of electrons.
b) _______ can also allow the movement of electrons when in liquids.
i) NaCl- Becomes _______ and ______ in water.
ii)
Joselyn J. Todd, Electricity Notes, Science 7, Cary Academy, 10.18.2004
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Name: _________________
Period: _________________
Date: __________________
2) ______ _ _____ hold the electrons in their orbit around the nucleus of an atom.
a)
b) The closer two oppositely charged particles are, the greater their attraction
for each other.
c) An ___________ surrounds every charged particle. This explains why
particles do not need to touch each other to be attracted towards one another
(balloon example.)
3) Insulators, Conductors, Semi-Conductors
a) ___________- A material where electrons can not easily move from place to
place.
i) These are the non-metals (17 elements) on the periodic table.
ii) Under the special conditions they can conduct electricity but generally
they are considered insulators.
iii) Materials such as ceramic, rubber, and wood are examples as well.
b) ___________- A material where electrons can easily move from place to place.
i) These are the most of the elements on the periodic table.
ii) Examples: copper, gold, aluminum, silver, and silicon (semiconductor).
c) _______________- A material whose electrical behavior is between that of a
conductor and an insulator at room temperature.
i) _________- Silicon is used to make many electronic devices, such as
transistors, electrical circuits, and computer chips.
ii) Examples: Silicon, Boron, Germanium, Arsenic
d) A electric wire- Inside is made of a metal (conductor) that conducts electricity
and the outside is made of rubber (an insulator).
4) Examples of _________________- Rapid movement of charge from one place to
another.
a) ________________: You become negatively charged due to a gain of
electrons while walking across the floor and then when you come close to
something which is positively charged there is a
_________________________.
b) Another example- lightning during a thunderstorm
c) ______________- The Earth acts as a huge conductor. Example- a lightning
rod made of metal conducts electricity from lightning away from your house
and instead, into the ground (Earth.)
Joselyn J. Todd, Electricity Notes, Science 7, Cary Academy, 10.18.2004
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Name: _________________
Period: _________________
Date: __________________
5) ________________- The flow of electric charge in a controlled manner. The
flowing charge is electrons. Example: the wires in your home that provide the
electric current for your TV, Computer, Etc.
a) ___________- Electrical charge must flow in a continuous, conducting loop.
b)
c) __________- the electrical potential of electrons (measured in Volts)
d) Electrons flow through a wire very slowly.
e) __________ work when the positive end is connected to the negative end
(where the electrons are until the circuit is completed) via a wire as seen in
the figure above.
i) The chemical reactions within the battery create the positive end/negative
end of the battery by producing electrons that are free to move when a
circuit is completed with the battery.
ii) There are many types of different batteries depending upon what
chemicals are within them.
f) __________- A measure of how difficult it is for electrons to flow, measured
in ________
i) Conductors have low resistance
ii) Insulators have high resistance
iii) The thinner the wire, the greater the resistance; the longer the wire, the
greater the resistance
Check your Understanding:
1. pp. 34-35
2. Do the following problems: 1, 2, 4, 5, 6, 9, 11, 12
Joselyn J. Todd, Electricity Notes, Science 7, Cary Academy, 10.18.2004
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