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Flashcards in D1 Deck (82)
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0
Q

Anything that occupies space or has mass is referred to as

A

Matter

1
Q

A substance that is made up of more than one type is a

A

Compound

2
Q

The atomic number of an element refers to the number of _____ in the ____ of an atom

A

Protons, nucleus

3
Q

The maximum number of electrons allowed in Valence orbit.

A

8

4
Q

In orbits farther from the nucleus, the energy possessed by electrons

A

Increases

5
Q

An electron that has broken loose from its atom is a

A

Free electron

6
Q

Semiconductors contain ____ valence electrons.

A

Four

7
Q

Most metals are good

A

Conductors

8
Q

The smallest independent portion that a substance can be broken down to is a

A

Molecule

9
Q

The smallest portion an element can be broken into

A

Atom

10
Q

Negative charge is called

A

Anion

11
Q

Positive charge is called

A

Cation

12
Q

The first Law

A

Like charges repel an unlike charges attract

13
Q

The force between two charges at rest is directly proportional to the product of the magnitudes of the charges and inversely proportional to the square of the distance between them.

A

Coulomb’s Law

14
Q

Each atom shares its valence electrons with others around it

A

Is a Metallic Bond

15
Q

An atom that has a positive charge possess _____ electrons then protons

A

Fewer

16
Q

Like charges ____ and unlike charges _____

A

Repel and attract

17
Q

Electrostatic charge becomes a hazard

A

Lightening and fuel handling

18
Q

The body can receive an electrostatic charge by

A

Friction (contact)
Conduction
Induction

19
Q

Electrons flow ____ to ____

A

(-) to (+)

Negative to positive

20
Q

A force that acts at a distance with no contact

A

A Field force

21
Q

____ refers to the charge at one point with respect to another

A

Polarity

22
Q

Two dissimilar materials rubbed together is the _____ effect

A

Triboelectric effect

23
Q

The work per unit charge done by a source of energy on electric charges, to move them against an electric field.

A

Electromotive Force (emf)

24
Q

Piezoelectric effect aka

A

Pressure

25
Q

Electrochemical effect aka

A

Chemical —> battery

26
Q

Thermoelectric effect aka

A

Heat

27
Q

Thermocouples used in series is called?

A

Thermopile

28
Q

Light

Extra energy causes the electrons to leave their atoms, and current to flow.

A

Photovoltaic effect

29
Q

Name of the device which uses the photovoltaic effect

A

Photovoltaic cell

30
Q

Magnetoelectric effect aka

A

Magnetism

31
Q

The law of the conservation of energy is

A

Energy may neither be created or destroyed

32
Q

6.24 X 10^18 is referred to as a

A

Coulomb

33
Q

The term used to represent opposition to current flow in a circuit

A

Resistance

34
Q

Charge

A

Q
Coulomb
C

35
Q

Power

A

P
Watt
W

36
Q

Resistance

A

R
Ohm
Upside down horseshoe

37
Q

Energy emf units

A

E
Volt
V

38
Q

Current units

A

I
Ampere
A

39
Q

Why diagram is easiest to understand for a person with little knowledge of electricity is a ____ diagram.

A

Pictorial

40
Q

A schematic diagram that shows power source as two vertical lines on either side is a ____ diagram

A

Ladder

41
Q

Difference between block diagram components and one-line diagram components.

A

Block diagram uses blocks.

One line diagram uses symbols.

42
Q

Schematic diagrams do not show

A

The physical relationship.

But rather the electrical relationship.

43
Q

Type of diagram where components are shown as they appear are _____ diagrams

A

Pictorial

44
Q

The flow chart style is the ____ diagram.

A

Block.

45
Q

Circuit map is a _____ type of diagram.

A

Wiring.

46
Q

Diagram with a three-dimensional component view is a ____ diagram.

A

Pictorial

47
Q

Does not show the individual conductors is a ____ diagram.

A

One-line or Block

48
Q

A device that changes electrical energy into other forms of energy is

A

a Load

49
Q

Define a short circuit

A

A parallel path of low resistance.

50
Q

Two types of damage due to high current

A

Thermal and Mechanical

51
Q

Current flows through a load from____ to ____

A

Negative to positive

-) to (+

52
Q

A charge at one point with respect to another.

A

Polarity

53
Q

How does a fuse or breaker protect from excessive current.

A

It creates an opening in the circuit

54
Q

When a switch is open it is____

A

Off

55
Q

Current flows through a power SOURCE from ____ to _____

A

Positive to negative

+) to (-

56
Q

Source, load and conductors are

A

The three necessary components to a circuit.

57
Q

To stop the load the switch must be____

A

Open

58
Q

why are resistors used

A

Creating heat
Regulating voltage
Controlling Current

59
Q

resistors are rated in

A

ohms and watts

60
Q

three types of resistors

A

wire-wound
film resistor
carbon composition

61
Q

Carbon composition has the ___watts rating

A

lowest

62
Q

Adjustable resistors are normally ___type

A

wire-wound

63
Q

More common name for an Edison fuse

A

plug fuse

64
Q

What was the fault with edison fuses

A

they could be replaced with one of a higher amperage

65
Q

A circuit breaker can operate on ___ or____

A

thermal or magnetic action

66
Q

knife blade fuses are used when the Amperage is in excess of

A

60A

67
Q

Trip- free means what?

A

that one can not hold the Breaker in the closed position once the circuit is tripped.

68
Q

CEC classes low voltage as

A

31V - 750V

69
Q

DRT cable is used for

A

ranges and dryers

70
Q

bus bars determine the ___rating of distribution panels

A

Amperage

71
Q

general service cables are common for

A

hard usage type for portable equipment

72
Q

each circular mil is = to ___square mils

A

0.7854

73
Q

Copper or aluminum which has the lower resistance

A

Copper

74
Q

R of Alumium = R of copper

A

x 1.64

so 10 ohms of copper x1.64 = 16.4 ohms aluminum

75
Q

5 factors that determine amps/ current flow in a conductor

A
type of conductor material
size
Insulation type
Ambient temperature
method of insulation.
77
Q

Atoms become stable if they have 8 electrons in their valence orbit. This is called

A

A Stable Octet

78
Q

Kirchhoff’s voltage law states that :

A

the sum of all voltages across resistors or loads is equal to the applied voltage

79
Q

_________ cannot be recharged, while ___________ can be recharged.

A

Primary cells, secondary cells

80
Q

Connecting cells in series (- to +) increases their ________, while connecting them in parallel (- to - and + to +) increases their

A

voltage rating, current rating

81
Q

The basic meter movement used for many analog instruments is.

A

the moving-coil galvanometer, or the D’Arsonval movement

82
Q

Voltage is measured in

Current is Measured in (devices)

A

Parallel

Series