final

Question 1

How does flux density affect magnetism

Answer 1

the more dense the magnetic lines of flux, the more magnetic field

Question 2

difference between magnetic and polar north pole

Answer 2

on opposite sides of the earth, magnetic is in south

Question 3

what direction does flux flow

Answer 3

north to south

Question 4

what is magnetomotive force

Answer 4

causes flux in a magnetive circuit

Question 5

what is an alteration

Answer 5

½ cycle of a sine wave

Question 6

what is the period of a sine wave

Answer 6

time required for 1 cycle

Question 7

what is a hertz

Answer 7

unit of measure for frequency

Question 8

what is frequency

Answer 8

number of complete cycles that occur in 1 sec

Question 9

what is the time for one cycle of a 300Hz sine wave

Answer 9

3.33mS 1 / 300

Question 10

what is the formula to calculate frequency

Answer 10

f=1/t

Question 11

when does the peak voltage of a sine wave occur

Answer 11

90 degrees

Question 12

What is peak to peak voltage

Answer 12

90 and 270 degrees

Question 13

what is root-mean-square voltage, and why is it used

Answer 13

RMS, makes AC voltage equivalent to DC voltage

.707xPv

Question 14

whats the equation for RMS voltage

Answer 14

.707xPv (peak voltage)

Question 15

handheld meters read what type of voltage

Answer 15

RMS

Question 16

what is inductance

Answer 16

opposes a change in current

Question 17

how is an inductor constructed

Answer 17

coils around a feral magnetic core

Question 18

4 factors that determine the amount of voltage inducted in a moving conductor

Answer 18

strength, length, speed, angles

Question 19

what is a henry

Answer 19

unit of measure for inductance

Question 20

difference between a relay and a solenoid, and when are they used

Answer 20

solenoid does mechanical work

relays are electrical switch

Question 21

how does the number of turns affect the inductance of a coil

Answer 21

more turns means more inductance

Question 22

at what point does a sine wave reach half peak value

Answer 22

30 degrees

Question 23

inductors oppose a change in _______

Answer 23

current

Question 24

when testing a coil with an ohmmeter, what type of reading should be expected

Answer 24

small amount of resistance at first

Question 25

calculate total inductance in series

Answer 25

add them up

Question 26

calculate total inductance in parallel

Answer 26

resipical

Question 27

equation for time constant for LR circuit

Answer 27

t=L/R

Question 28

equation for time constant for CR circuit

Answer 28

t=RxC

Question 29

unit for measure that uses L

Answer 29

inductor; same as resistance

Question 30

unit for measure that uses capacitance

Answer 30

farads

Question 31

time constance that are required to achieve maximum current flow in an inductive circuit

Answer 31

5x

Question 32

what is the percentage for the first time constant, first discharge

Answer 32

63 percent | 37 percent

Question 33

how is a capacitor constructed

Answer 33

2 metal plates separated by a dielectric

Question 34

compare how a capacitor stores energy compared to an inductor

Answer 34

Cap= electrostatic field | Induct=electromagnetic field

Question 35

what is the dc resistance of a normally operating capacitor

Answer 35

capacitors block DC

Question 36

how do u test a capacitor with an ohm meter and whats the results

Answer 36

volts? reads as an open circuit (OL)

Question 37

how does the size of the plates and the distance between the plates affect capacitance

Answer 37

bigger/closer the plates more capacitance, farther away more voltage

Question 38

what is the dielectric, and what type of resistance does it have

Answer 38

insulating material | infinite resistance

Question 39

calculate the total capacitance in series

Answer 39

resipical

Question 40

calculate the total capacitance in parallel

Answer 40

add them up

Question 41

capacitors oppose a change in_______

Answer 41

voltage

Question 42

what is a working voltage of a capacitor

Answer 42

peak amount of voltage it can use before breaking down | WV (working voltage)

Question 43

time constant formula for a RC circuit

Answer 43

t=RxC

Question 44

in a capacitive circuit the _____ leads the ______

Answer 44

current, voltage

Question 45

how many zener diodes are needed to make a bridge recifier

Answer 45

0 only diodes make a rectifier

Question 46

what is the difference between the primary and the secondary of a transformer

Answer 46

primary is the input voltage and secondary is the output voltage

Question 47

how does the winding ratio affect the voltage of the transformer

Answer 47

makes it a step up or step down transformer

Question 48

how does the winding ratio affect the power of the transformer

Answer 48

it does not effect it | P:in=P:out

Question 49

will a transformer work with a DC power source

Answer 49

NO

Question 50

compare a step down transformer to a step up transformer

Answer 50

step down, less voltage more current | step up, more voltage less current

Question 51

law of power with the regard to the primary and secondary of a transformer

Answer 51

P:in=P:out | power in equals power out

Question 52

calculate the secondary current flow for a step up transformer 1:5. secondary load is 220 ohm, primary voltage 120V

Answer 52

2.73A

Question 53

what is the value of a capacitor labeled 922 | 763

Answer 53

9200pf | 76000pf

Question 54

what are the units of measurement for Xl,Xc,Z

Answer 54

ohms

Question 55

a series RL circuit has an impedance of 520 ohms at a phase angle of 42 degrees. what is the circuit resistance

Answer 55

386.44 ohms

Question 56

what are the 3 sides of the power factor triangle | draw and label where everything are on the triangle

Answer 56

VA, VARS, WATTS

Question 57

how is the power factor calculated

Answer 57

true/apparrent x 100 percent