Electrical Units

Question 0

Milli

Answer 0

.001 or a thousandth

Question 1

A potential difference between two points produces an __________.

Answer 1

Electric Field

Question 2

Micro

Answer 2

.0000001 or a millionth

Question 3

Kilo

Answer 3

1000 or a thousand

Question 4

Mega

Answer 4

1,000,000 or a million

Question 5

The largest voltages (tens of mega volts) on earth occur in ___________.

Answer 5

Clouds

Question 6

_______ represents the pressure or driving force that impels the charge carriers to move.

Answer 6

Voltage

Question 7

__________ is the flow of charge carries attempting to equalize the charge between two poles that have a potential difference.

Answer 7

Current

Question 8

__________ is the measure of of the opposition that a circuit offers to the flow of electric current.

Answer 8

Resistance

Question 9

The standard unit of resistance is the ________.

Answer 9

Ohm

Question 10

The larger the current through a resistor the greater the __________ through that same resistor.

Answer 10

Electromotive Force (EMF)

Question 11

When some metals are chilled to extremely low temperatures they become ____________ which are almost perfect, resistance-free conductors.

Answer 11

Superconductors

Question 12

___________ is the ability a material has to conduct electricity.

Answer 12

Conductance

Question 13

Conductance is measured in ___________.

Answer 13

Siemens

Question 14

1 Siemens is ________ ohm

2 Siemens is ________ ohm

Answer 14

1

1/2

Question 15

What is the formula for Siemens/Ohms?

Answer 15

Siemens = 1/Ohms

Ohms = 1/Siemens

Question 16

Unlike with resistance, conductance will _____________ with wire length.

Answer 16

Decrease

Question 17

Whenever current flows through a resistance, _________ results. This heat can be measured in _________ and represents electrical __________.

Answer 17

Heat

Watts

Power

Question 18

What is the formula for Power?

Answer 18

Power = Volts x Current (P = V x I)

Question 19

Pico

Answer 19

.0000000000001 or one trillionth

Question 20

Nano

Answer 20

.0000000001 or one billionth

Question 21

Energy is _________ dissipated over a period of time.

Answer 21

Power

Question 22

Power is the rate at which __________ is expended.

Answer 22

Energy

Question 23

Physicists measure energy in _________.

Answer 23

Joules

Question 24

One joule is one ________ of power dissipated for one _________ of time.

Answer 24

Watt Second

Question 25

ERG

Answer 25

One ten millionth (.0000001) of a Joule

Question 26

___________ is the cooling or heating capacity of air conditioning equipment.

Answer 26

British Thermal Unit or BTU (1055 Joules)

Question 27

_____________ is the energy gained by a single electron in a energy field of 1 volt.

Answer 27

Electron Volt or eV is 1.6 x 10^-19 Volts or (.00000000000000000016)

Question 28

Joules to BTU Formula

Answer 28

Joules x 1055 = BTU

Question 29

BTU to Joules Formula

Answer 29

BTU x .000948 = Joules

Question 30

kWh to Joules Formula

Answer 30

kWh x 3,600,000 (3.6 x 10^6) = Joules

Question 31

Joules to kWh (kilo Watt hours) Formula

Answer 31

Joules x .000000278 (2.78 x 10^-7) = kWh

Question 32

(Watt Hours) Wh to Joules Formula

Answer 32

Wh x 3600 = Joules

Question 33

__________ current is current that always flows in the same direction.

Answer 33

Direct

Question 34

_______ current reverses direction periodically exactly every 1/120 second. It goes thru a complete cycle every 1/60 second.

Answer 34

Alternating

Question 35

The ________ voltage for an ac wave is never the same as the __________ maximum, or peak, voltage.

Answer 35

Effective Instantaneous

Question 36

For the common ac waveform the effective value is __________ times the peak value.

Answer 36

.707

Question 37

The peak value of a common waveform is _________ times the effective value.

Answer 37

1.414

Question 38

The __________ of the utility ac wave is 60 __________ (once every 1/60 seconds).

Answer 38

Frequency Hertz

Question 39

Usually, but not always, ac waveforms are known as __________ wave or a ___________ wafeform.

Answer 39

Sine Sinusoidal

Question 40

___________ is a process in which ac is changed to dc.

Answer 40

Rectification

Question 41

When a special core (like iron or any substance that can be readily magnetized) is placed inside a coil, this will greatly increase the magnetic field. Such substances are called ___________.

Answer 41

Ferromagnetic

Question 42

The size of a magnetic field is measured in units called _________.

Answer 42

Webers

Question 43

One weber is mathematically equivalent to one _________.

Answer 43

Volt second

Question 44

One __________ is equivalent to .00000001 (one hundredth millionth) of a weber or .01 micro volt second.

Answer 44

Maxwell

Question 45

Whenever an electric current flows a ____________ field accompanies the current.

Answer 45

Magnetic

Question 46

Magnetic fields have lines of ________ that surround the wire in circles.

Answer 46

Flux

Question 47

The ___________ density of a magnetic field is given in terms of webers or maxwells per square meter or per square centimeter.

Answer 47

Flux

Question 48

A __________ has one weber per square meter (1 Wb/m2) a flux density

Answer 48

Tesla

Question 49

One __________ is equal to .0001 weber or one maxwell per square centimeter.

Answer 49

Gauss

Question 50

The greater the electric current through a wire, the greater the ___________ near the wire.

Answer 50

Flux Density

Question 51

A __________ wire will produce a greater flux density than a straight wire.

Answer 51

Coil

Question 52

Sometimes magnetic field strength is specified by ______ turns, a unit of __________ force.

Answer 52

Ampere Magnetomotive

Question 53

A one turn wire loop, carrying a 1 amp of current, produces a field of _____ At (ampere turn).

Answer 53

One (Turns x Current = At (Ampere turns))

Question 54

Another unit of magnetomotive force is the _______.

Answer 54

Gilbert = .796 At (Ampere turns)

Question 55

The unbalanced FORCE that imparts an ACCELERATION of 1 METER PER SECOND SQUARED to a MASS of 1 kilogram Equation: Force = 1 Kg x m/s^2

Answer 55

Newton (N)

Question 56

________ results when a FORCE acts over a DISTANCE Joules ( _____ ) = N (FORCE) x m (DISTANCE)

Answer 56

Work

Question 57

Work and ________ use the JOULE as the unit a measurement

Answer 57

Energy

Question 58

The RATE at which WORK is done OR the RATE at which ENERGY is changed from one form to another Joules / sec

Answer 58

Power (W)

Question 59

Quantity: ________ Symbol: Q, q SI Unit: Coulomb Abbreviation: __

Answer 59

Electric Charge C

Question 60

Quantity: _______ Symbol: R SI Unit: ____ Abbreviation: Ω

Answer 60

Resistance Ohms

Question 61

Quantity: _________ Symbol: G SI Unit: Siemens Abbreviation: ___

Answer 61

Conductance S

Question 62

Quantity: Electric Potential Symbol: _____ SI Unit: Volt Abbreviation: V

Answer 62

V

Question 63

Quantity: Inductance Symbol: ___ SI Unit: ________ Abbreviation: H

Answer 63

L Henry

Question 64

Quantity: Capacitance Symbol: C SI Unit: ____ Abbreviation: F

Answer 64

Farad

Question 65

Quantity: Frequency Symbol: f SI Unit: _______ Abbreviation: ___

Answer 65

Hertz Hz

Question 66

Quantity: Force Symbol: F, f SI Unit: __________ Abbreviation: ___

Answer 66

Newton N

Question 67

Quantity: Energy/Work Symbol: W, w SI Unit: ________ Abbreviation: ___

Answer 67

Joule J

Question 68

Quantity: Power Symbol: P, p SI Unit: ______ Abbreviation: ____

Answer 68

Watt W

Question 69

Quantity: Magnetic Flux Symbol: Ø SI Unit: ________ Abbreviation: ___

Answer 69

Weber Wb

Question 70

Quantity: Length Symbol: ________ SI Unit: ______ Abbreviation: _____

Answer 70

L, l Meter m

Question 71

Quantity: Mass Symbol: M, m SI Unit: ______ Abbreviation: ____

Answer 71

Kilogram kg

Question 72

Quantity: Time Symbol: T, t SI Unit: _____ Abbreviation: ___

Answer 72

Seconds s

Question 73

Quantity: Current Symbol: I, i SI Unit: ________ Abbreviation: _____

Answer 73

Ampere A

Question 74

Quantity: Magnetic Flux Density Symbol: B SI Unit: _______ Abbreviation: ___

Answer 74

Tesla T

Question 75

Prefix: pico Factor: _____ Symbol: p

Answer 75

10^-12 .000000000001 (Trillionth)

Question 76

Prefix: ____ Factor: 10^-9 Symbol: __

Answer 76

nano n .000000001 (Billionth)

Question 77

Prefix: micro Factor: _________ Symbol: µ

Answer 77

10^-6 .000001 (Millionth)

Question 78

Prefix: milli Factor: _______ Symbol: ______

Answer 78

10^-3 m .001 (Thousandth)

Question 79

Prefix: _______ Factor: 10^-2 Symbol: _____

Answer 79

centi c .01 (Hundredth)

Question 80

Prefix: deci Factor: ____ Symbol: ___

Answer 80

10^-1 d .1 (Tenth)

Question 81

Prefix: ______ Factor: 10^3 Symbol: ___

Answer 81

kilo k 1000 (Thousand)

Question 82

Prefix: ____ Factor: 10^6 Symbol: ____

Answer 82

mega M 1000000 (Million)

Question 83

Prefix: giga Factor: _______ Symbol: G

Answer 83

10^9 1000000000 (Billion)

Question 84

Prefix: ___ Factor: _______ Symbol: T

Answer 84

tera 10^12 1000000000000 (Trillion)

Question 85

Prefix: yocto Factor: _____ Symbol: y

Answer 85

10^-24 .000000000000000000000001 (Septillionth)

Question 86

Prefix: zepto Factor: 10^-21 Symbol: ____

Answer 86

z .000000000000000000001 (Sextillionth)

Question 87

Prefix: atto Factor: ______ Symbol: a

Answer 87

10^-18 .000000000000000001 (Quintillionth)

Question 88

Prefix: femto Factor: ______ Symbol: ____

Answer 88

10^-15 f .000000000000001 (Quadrillionth)

Question 89

Prefix: deka Factor: _____ Symbol: ____

Answer 89

10^1 D 10 (Ten)

Question 90

Prefix: hecto Factor: ____ Symbol: ____

Answer 90

10^2 h 100 (Hundred)

Question 91

Prefix: peta Factor: ____ Symbol: ____

Answer 91

10^15 P 1000000000000000 (Quadrillion)

Question 92

Prefix: exa Factor: ____ Symbol: E

Answer 92

10^18 1000000000000000000 (Quintillion)

Question 93

Prefix: zetta Factor: _____ Symbol: Z

Answer 93

10^21 1000000000000000000000 (Sextillion)

Question 94

Prefix: yotta Factor: ______ Symbol: _____

Answer 94

10^24 1000000000000000000000000 (Septillion)