Navedtra 14173 Neets Module 1 Chapter 1

Front 1

What is matter, and in what three states is it found?

Back 1

Matter is defined as anything that occupies space and has weight; SOLID, LIQUID, and
GASEOUS

Front 2

What is an element?

Back 2

An ELEMENT is a substance which cannot be reduced to a simpler substance by chemical means

Front 3

What is a compound?

Back 3

A compound is a chemical combination of elements which can be separated by chemical
but not by physical means

Front 4

What is the difference between a compound and a mixture?

Back 4

Compounds are chemically combined and cannot be seperated by physical means, while mixtures are not chemically combined and can be seperated by physical means.

Front 5

What is a molecule?

Back 5

A MOLECULE is a chemical combination of two or more atoms

Front 6

What are the three types of subatomic particles, and what are their charges?

Back 6

The atoms of each element are made up of electrons(negative), protons(positive), and, in most cases, neutrons(neutral), which are
collectively called subatomic particles.

Front 7

What is energy of motion called?

Back 7

Energy of motion is called KINETIC ENERGY

Front 8

How is invisible light changed to visible light in a fluorescent light?

Back 8

This principle is used in the fluorescent light where ultraviolet light photons, which are not visible to
the human eye, bombard a phosphor coating on the inside of a glass tube. The phosphor electrons, in
returning to their normal orbits, emit photons of light that are visible.

Front 9

What determines the valence of an atom?

Back 9

The number of electrons in the outermost shell determines the valence of an atom.

Front 10

What is an ion?

Back 10

When the atom loses electrons or gains electrons in this process of electron exchange, it is said to be
IONIZED

Front 11

What determines whether a substance is a conductor or an insulator?

Back 11

The number of valence electrons.

Front 12

How is a negative charge created in a neutral body?

Back 12

Through the accumulation of excess electrons.

Front 13

How are static charges created?

Back 13

By friction.

Front 14

What is the electrical charge of an atom which contains 8 protons and 11 electrons?

Back 14

Negative.

Front 15

What is the relationship between charged bodies?

Back 15

Like charges repel, and unlike charges attract with a force directly proportional to the product of
their charges and inversely proportional to the square of the distance between them.

Front 16

What is an electrostatic field?

Back 16

The space between and around charged bodies.

Front 17

In what direction are electrostatic lines of force drawn?

Back 17

Leaving positive, entering negative.

Front 18

What are some examples of electrical equipment which use magnetism?

Back 18

Motors, generators, speakers, computers, televisions, tape recorders, and many others

Front 19

What are magnetic materials?

Back 19

Those materials that are attracted by magnets and have the ability to become magnetized

Front 20

What characteristics do all ferromagnetic materials have in common?

Back 20

The relative ease with which they are magnetized.

Front 21

What type of magnetic material should be used to make a temporary magnet?

Back 21

A material that exhibits low reluctance and high permeability, such as iron or soft steel.

Front 22

What is retentivity?

Back 22

The ability of a material to retain magnetism.
A23. They are very similar; like charges repel, unlike

Front 23

How does the law of magnetic poles relate to the law of electric charges?

Back 23

They are very similar; like charges repel, unlike charges attract, like poles repel—unlike poles
attract.

Front 24

A compass is located at the geographical North Pole. In which direction would its needle point?

Back 24

To the magnetic north pole.

Front 25

Using Weber's molecular theory of magnetism, describe the polarity of the magnetic poles
produced by stroking a magnetic material from right to left with the south pole of a magnet.

Back 25

South pole at the right, north pole at the left.

Front 26

What is the difference between the domain theory and Weber's theory of magnetism?

Back 26

The domain theory is based upon the electron spin principle; Weber,s theory uses the concept of
tiny molecular magnets.

Front 27

What is a magnetic line of force?

Back 27

An imaginary line used to illustrate magnetic effects.

Front 28

In what way do magnetic lines of force differ from electrostatic lines of force?

Back 28

Electrostatic lines of force do not form closed loops.

Front 29

How should a delicate instrument be protected from a magnetic field?

Back 29

By shielding or surrounding the instrument with a soft iron case, called a magnetic shield or
screen.

Front 30

How should bar magnets be stored?

Back 30

In pairs, with opposite poles together to provide a complete path for magnetic flux.

Front 31

What is the definition of energy?

Back 31

The ability to do work.

Front 32

What type of energy does a rolling stone have?

Back 32

Kinetic energy.

Front 33

What kind of energy does the stone have if it is at rest at the top of a hill?

Back 33

Potential energy.

Front 34

What term describes voltage or emf?

Back 34

Difference of potential.

Front 35

Convert 2.1 kV to volts.

Back 35

2100 volts.

Front 36

Express the following in more simple terms. (a) 250,000 volts, (b) 25,000,000 microvolts, (c)
0.001 millivolt.

Back 36

(a) 250 kV, (b) 25 V, (c) 1 μV.

Front 37

A device which supplies a voltage is commonly referred to by what name?

Back 37

A voltage source.

Front 38

Name the six methods of producing a voltage.

Back 38

Friction, pressure, heat, light, chemical action, and magnetism.

Front 39

The piezoelectric effect is an example of a voltage being produced by what method?

Back 39

Pressure.

Front 40

A thermocouple is a device that produces voltage by what method?

Back 40

Heat.

Front 41

A battery uses what method to produce a voltage?

Back 41

Chemical.

Front 42

A generator uses what method to produce a voltage?

Back 42

Magnetic.

Front 43

According to electron theory, an electric current flows from what potential to what potential?

Back 43

Electron theory assumes that electron flow is from negative to positive.

Front 44

The effects of directed drift take place at what rate of speed?

Back 44

The speed of light (186,000 miles per second, 300,000,000 meters per second).

Front 45

What is the relationship of current to voltage in a circuit?

Back 45

Current increases as voltage increases.

Front 46

Convert 350 mA to amperes.

Back 46

0.35 amperes.

Front 47

What is the symbol for ohm?

Back 47

Ω

Front 48

When would silver be used as a conductor in preference to copper?

Back 48

When the need for conductivity is great enough to justify the additional expense.

Front 49

Which wire has the least resistance? Wire A-copper, 1000 circular mils, 6 inches long. Wire
B-copper, 2000 circular mils, 11 inches long.

Back 49

Wire B.

Front 50

Which temperature coefficient indicates a material whose resistance increases as temperature
increases?

Back 50

Positive.

Front 51

What term describes a material whose resistance remains relatively constant with changes in
temperature?

Back 51

Zero temperature coefficient.

Front 52

What is the unit of conductance and what other term is sometimes used?

Back 52

The mho (v), siemens.

Front 53

What is the relationship between conductance and resistance?

Back 53

They are reciprocals of each other.

Front 54

What is schematic symbol for a resistor?

Back 54

-^^^-

Front 55

What does the wattage rating of a resistor indicate?

Back 55

Its ability to dissipate heat.

Front 56

What are the two disadvantages of carbon-type resistors?

Back 56

1. Change value with age. 2. Limited power capacity.

Front 57

What type resistor should be used to overcome the disadvantages of the carbon resistor?

Back 57

The wirewound resistor.

Front 58

Describe the differences between the rheostat connections and those of the potentiometer.

Back 58

The rheostat may have two connections, one fixed and one moveable; the potentiometer always
has three connections, one moveable and two fixed.

Front 59

Which type of variable resistor should you select for controlling a large amount of current?

Back 59

The rheostat.

Front 60

A carbon resistor has a resistance of 50 ohms, and a tolerance of 5 percent. What are the colors of
bands one, two, three, and four, respectively?

Back 60

The bands are green, black, black, and gold.

Front 61

A carbon resistor has the following color bands: The first band is yellow, followed by violet,
yellow, and silver. What is the ohmic value of the resistor?

Back 61

470,000 ohms (470 kilohms).

Front 62

The same resistor mentioned in question 63 has a yellow fifth band. What does this signify?

Back 62

The resistor,s chance of failure is 0.001 percent for 1000 hours of operation.

Front 63

A resistor is handed to you for identification with the following color code: the first band is blue,
followed by gray, green, gold, and brown. What is the resistor,s value?

Back 63

6,800,000 ohms (6.8 megohms), with 5% tolerance, and a 1% reliability level.