Download unit d: electrical principles and technology

ELECTRICAL PRINCIPLES AND TECHNOLOGY VOCABULARY Answer Key
Name: ____________________________________ Homeroom: __________
Topic A Vocabulary:
Energy
Kinetic energy
Potential energy
Mechanical energy
Positive terminal
Radiant energy
Solar cell
Chemical energy
Electrical energy
Thermal energy
Thermocouple
Nuclear energy
Generator
Michael Faraday
Electromagnetic induction
Turbine
Hans Oersted
Power plant
Motor
Electromagnet
Power grid
Polarity
Terminal
Brushes
Commutator
Armature
Permanent magnets
Cell
Battery
Electrodes
Coal
Electrolyte
Wet cell
Dry cell
Photovoltaic cell
photons
Negative terminal
1. Some common sources of energy that can be
converted from one form to another are
electrical (energy of charged particles),
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chemical (energy of chemical reactions),
mechanical (energy of moving objects), nuclear
(energy of atoms), or thermal (energy of heat).
2. A device that can convert thermal energy into electrical
energy by heating two different kinds of metal is a
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thermocouple.
3. A magnet that can have its power turned on and off or made
stronger or weaker by current is called an electromagnet.
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Michael Faraday was the first person to notice that
electromagnetic properties of a wire carrying an electrical
current could cause continuous motion.
4. Energy from our Sun is called radiant energy and it can
be converted to useful electrical energy using a solar
cell. The energy is in the form of photons which is why a
solar cell is often called a photovoltaic cell.
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Illustration
5. Michael Faraday discovered electromagnetic induction when
he moved a magnet through a coil of wire and voltage
registered in the circuit. This led to the discovery of the
generator.
6. In Alberta, coal is burned and used to create steam, which
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turns a turbine, which then turns the generator. The
building where this occurs is called a power plant. The
electricity generated is sent on to homes and businesses.
This is all part of our power grid.
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7. Energy is the ability to do work. Kinetic energy is actually
working and causing change while potential energy is
available when needed but not currently working.
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8. The parts of a motor which is a device for converting
mechanical to electrical energy are: the brushes (carry
current from source into motor), the commutator
(alternately switches polarity of current flow to the
electromagnets) the armature (spins and turns attached
mechanisms) and the permanent magnets (attracts the
electromagnets on either side of the armature).
9. You can change the direction a motor turns by changing the
polarity. This is done by reversing the wire connections on
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the terminals.
10. Cells are designed to convert chemical energy into small
amounts of electrical energy.
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11. All cells have two different metals making up their
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electrodes and an ionic conductor (acid or base) called
the electrolyte which is in contact with the metal
strips.
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12. Two or more cells connected together are called a battery.
13. Dry cells have an electrolyte in paste form and wet cells
have an electrolyte in liquid form.
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Illustration
14. Energy always flows from the negative terminal toward the
positive terminal in a cell.
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15. Hans Oersted noticed that when he brought a compass near
to a wire carrying an electrical current, the compass needle
was deflected. This led to the invention of the electromagnet.
Topic B Vocabulary:
Short circuit
Voltage
Amperage
Fuse
Circuit breaker
Ground wire
Static electricity
Current electricity
Insulator
Conductor
Lie detector
Semi-conductor
Super-conductor
Resistor
Nichrome wire
Tungsten wire
Circuit symbol
Circuit diagram
Switch
Rheostat
Dimmer switch
Source
Variable resistor
three-way switch
Photocell
Ohm’s Law
Volts
Amps
Ohms
Voltmeter
Ammeter
Ohmmeter
Multimeter
Galvanometer
Load
Parallel circuit
Series circuit
Microelectronic circuit
Transistor
16. Electricity that is stationary until it builds to a high enough
energy level to suddenly discharge is called static
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electricity.
17. Voltage is the energy of each charged particle (its strength)
and it is measured in volts using a voltmeter.
Illustration
18. The mathematical relationship between voltage, current and
resistance (V = I x R) is called Ohm’s Law.
Illustration
19. Amperage is the rate at which charged particles move (how
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many pass a point in a given time) and it is measured in amps
using an ammeter.
20. Ground wires are designed to give electricity a pathway
away from people and down into the ground in case there is a
short circuit.
21. A three-way-switch allows a person to turn on or off a
light from different locations.
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Illustration
Illustration
22. Fuses are designed to melt if too much current passes
through them. This keeps a circuit from heating up to the
point where it could start a fire.
23. Circuit breakers in buildings have switches that flip off if
a metal strip bends too much through excess heat. This
shuts the circuit off before it can get too hot and cause a
fire.
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Illustration
24. When electricity flows as a steady stream of charged
particles through a conductor it is called current
electricity.
25. Current electricity always wants to take the shortest
pathway and when it gets a chance to do this through a
conductor other than its normal path (including through you
if you get in the way), it is called a short circuit.
Illustration
Illustration
26. Common electrical measuring devices are multimeters
which measure voltage, current and resistance. A
galvanometer is a device used to detect very small amounts
of current and can be made using a compass and a piece of
wire.
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27. Materials such as copper that easily allow the flow of
charged particles are called conductors.
28. Materials such as rubber that do no allow the flow of
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charged particles are called insulators.
29. Materials such as silicon that have properties of both
resistors and conductors are called semi-conductors.
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Illustration
30. Super conductors are almost perfect conductors at very
cold temperatures, offering little or no resistance to
current flow.
Illustration
31. A cell that acts like a switch when it is activated by light
energy is called a photocell and is often used for automatic
doors and motion lights.
Illustration
32. A conductor that is more difficult to flow through and
therefore uses up more energy, such as nichrome wire or
tungsten wire, is called a resistor.
33. The unit for measuring resistance is the ohm and it is
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measured using an ohmmeter. The opposite of resistivity is
conductivity which measures how well a material conducts
energy.
34. A rheostat or dimmer switch allows a load in a circuit to
have varying amounts of electrical energy so lights will dim
and brighten, speakers will get louder and more quiet and
motors will go faster and slower. This is also sometimes
called a variable resistor.
35. A schematic diagram of the components making up an
electrical circuit is called a circuit diagram. Each
Illustration
Illustration
individual component is represented by a circuit symbol.
36. Every circuit must have at least one energy source, a
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load which converts
electrical energy to another form of energy and a switch to
conductive pathway for current, a
start and stop the current.
37. A circuit that has all loads in succession along one pathway is
called series circuit.
Illustration
Illustration
38. A circuit where each load has its own pathway back to a
source is called parallel circuit.
39. Microelectronic circuits contain tiny resistors (control
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amount of current flow) and transistors (act as complex
switches) are the primary parts of electronic circuits.
40. A device that uses the fact that sweaty skin is more
conductive than dry skin in order to tell if a person is being
truthful is called a lie detector.
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Topic C Vocabulary:
Input energy
Output energy
Transformer
Joules
Megajoule
Kilojoule
Power
Watt
Kilowatt hour
Efficiency
Energuide label
Incandescent bulb
Fluorescent bulb
Friction
Energy Kilowatt
Megawatt
41. The rate at which energy is converted is called power and it is
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measured in watts, kilowatts (1000 watts) or megawatts (1
000 000 watts).
42. Energy is the ability to do work and it is measured in joules,
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kilojoules (1000 joules) or megajoules (1 million joules).
43. For convenience is determining the amount of energy used by
households and businesses, meters are set to read kilowatt
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hours rather than joules but they are calculated the same
way.
44. The efficiency of most incandescent bulbs is not very good
(only 5%) because a great deal of the input energy goes to
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producing output heat energy rather than light. Fluorescent
bulbs are slightly more efficient (20%),
45. The energy required to make an electrical device operate is
called the input energy while the amount of useful work you
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get out of it is called output energy. The greatest cause of
differences between these is friction which produces wasted
heat energy.
46. All appliances must have an Energuide label to let consumers
know how efficient it is.
47. A transformer is used to change voltage from high to low, or
from low to high. These are the green boxes you see in
neighbourhoods.
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Illustration
Topic D Vocabulary:
Fossil fuel
Wind generator
Wave generator
Biomass
Fuel cell
Nuclear
Renewable resource
Non-renewable resource
Sulfur dioxide
Nitrogen oxide
Greenhouse gas
Fly ash
Binary system
Carbon monoxide
Geothermal
Sustainability
Carbon dioxide
Solar
48. Producing electrical energy can pollute the environment
through chemicals such as sulfur dioxide (produces
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acid rain) and carbon dioxide which is the
greenhouse gas at least partially to blame for global
warming.
49. Rather than burning fossil fuels to produce steam,
some cleaner alternative energy sources include
geothermal (heat from Earth’s core), nuclear (heat
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from splitting atoms), biomass (heat from rotting
garbage) or solar (light from sunlight).
50. Sustainability refers to the choice to use resources in a
responsible manner so that they will be available to future
generations.
51. Renewable resouces are able to be replaced during a
person’s lifetime so that energy sources are available while
non-renewable resources will take more than a generation
to be replaced (maybe never).
52. One of the worst polluting energy sources are fossil
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Illustration
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fuels which must be burned to produce energy,
releasing a variety of toxins including nitrogen oxide
which causes the brown smog in cities and fly ash
which is dust containing arsenic.
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53. Wind generators (using power from the wind) and wave generators
(using power from the waves) are to renewable energy options.
54. One day cars will probably be powered by fuel cells which use
hydrogen as an energy source but there are still too many
safety concerns to make it practical at this time.
55. Most electronic information is written using a simple two digit
code of “0” and “1”. This is called a binary code.
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