chapter 29 powerpoint

Question 1

Electrical circuits range from simple to complex. Simple circuits may only have a _________, ________, and ________.

Answer 1

power supply, switch, and load

Question 2

Power supply may be a DC, AC, DC to AC, or AC to DC power supply.

Answer 2

DC, AC, DC to AC, or AC to DC power supply.

Question 3

any device that converts electrical energy to motion, heat, light, or sound.

Answer 3

Load

Question 4

What are common examples of loads?

Answer 4

Common examples: heating coils, lamps, speakers, and motors

Question 5

___________ and _________ affect electrical circuits differently than only _________.

Answer 5

Inductance (L)
capacitance (C)
resistance (R)

Question 6

Resistance, inductance, and capacitance must all be considered when analyzing a circuit that is more than just a ________.

Answer 6

resistive load

Question 7

A circuit that contains only resistive components, such as heating elements, and incandescent lamps.

Answer 7

resistive circuits

Question 8

P=

Answer 8

E x I

Question 9

I=

Answer 9

E / R

Question 10

a material that has very little resistance and permits electrons to move through it easily.

Answer 10

Conductor

Question 11

All electrical circuits use ________ to carry electricity to different parts of the circuit.

Answer 11

conductors

Question 12

The resistance of any conductor with a uniform cross-sectional area is based on:

Answer 12

1. Material Temperature
2. Conductor Size
3. Conductor Length
4. Material

Question 13

the resistance of a conductor having a specific length and cross-sectional area

Answer 13

Conductor Resistance

Question 14

the property of a circuit that causes it to oppose a change in current due to energy stored in a magnetic field.

Answer 14

Inductance (L)

Question 15

is the unit of inductance

Answer 15

Henry (H)

Question 16

Henrys

Answer 16

(H)

Question 17

Millihenrys

Answer 17

(mH)

Question 18

Microhenrys

Answer 18

(μH)

Question 19

The inductance in a coil is __ when the change in current is 1 A/sec and the induced voltage is 1 V.

Answer 19

1H

Question 20

The amount of inductance produced by a coil depends on the strength of the ___________ produced by the coil.

Answer 20

magnetic field

Question 21

Factors that determine a coil’s inductance include:

Answer 21

1. Number of turns in the coil
2. Length and spacing of the coil
3. Core material and relative permeability of the core material
4. Size of the wire used to make the coil.

Question 22

Is added to fluorescent and HID lamp circuits to provide a high-voltage starting surge and limit current flow.

Answer 22

ballast

Question 23

operate on the same basic electrical principles of magnetism as transformers

Answer 23

Inductors

Question 24

Inductors

Answer 24

one coil

Question 25

Transformers

Answer 25

use two or more coils

Question 26

an inductor’s opposition to alternating current. Is measured in ohms Depends on: 1. The amount of inductance (H) of the coil. 2. Frequency of the current

Answer 26

Inductive reactance (XL):

Question 27

is measured in ohms and can be determined when the values of inductance and frequency are known.

Answer 27

Inductive reactance

Question 28

The formula for determining inductance reactance is:

Answer 28

XL = 2πf L

Question 29

XL = 2πf L | XL =

Answer 29

inductive reactance in Ω

Question 30

XL = 2πf L | 2π =

Answer 30

6.28 (indicates the circular motion that produces the AC sine wave)

Question 31

XL = 2πf L | f =

Answer 31

applied frequency in Hz

Question 32

XL = 2πf L | L=

Answer 32

inductance in H

Question 33

To calculate inductive reactance when voltage across a coil (EL) and current through a coil (IL) are known or measured:

Answer 33

XL = "EL" /"IL"

Question 34

XL = "EL" /"IL" | XL=

Answer 34

XL = inductive reactance in Ω

Question 35

XL = "EL" /"IL" | EL=

Answer 35

EL = voltage across coil in V

Question 36

XL = "EL" /"IL" IL=

Answer 36

IL = current through coil in A

Question 37

1. At zero frequency, there is no opposition due to inductance. 2. A coil has low resistance and no inductive reactance 3. Current flow through a coil connected to __ is limited only by the resistance of the wire.

Answer 37

DC resistance

Question 38

Inductance: Series Inductive Reactance The inductive reactance of a circuit containing more than one coil is found by first determining the _________ of the circuit and then calculating the inductive reactance.

Answer 38

total inductance

Question 39

The total inductance in a circuit containing parallel-connected coils is less than the ___________.

Answer 39

smallest coil value

Question 40

The total inductance of two coils connected in parallel is found by applying the same formula for calculating the _______________connected din parallel.

Answer 40

the resistance of two loads

Question 41

the ability of a component or circuit to store energy in the form of an electrical charge.

Answer 41

Capacitance (C):

Question 42

an electric device specifically designed to store a charge of energy.

Answer 42

Capacitor:

Question 43

What is the unit for capacitators?

Answer 43

farad (F)

Question 44

Too large for most electrical/electronic applications. Normally stated in microfarads (μF) or picofarads (pF).

Answer 44

farad (F)

Question 45

The amount of capacitance a capacitor has is determined by:

Answer 45

1. The area of the plates 2. The spacing between the plates 3. The dielectric used 4. Connection arrangement

Question 46

a capacitor that has one value of capacitance.

Answer 46

Fixed capacitator

Question 47

a capacitor that varies in capacitance value.

Answer 47

Variable capacitator

Question 48

Current in a capacitor can only flow during the time period when the capacitor is either being ____________________.

Answer 48

charged or discharged

Question 49

A capacitor is created by separating strips of metal with a _____________________.

Answer 49

dielectric or insulating material

Question 50

the total opposition to the flow of alternating current that consists of any combination of resistance, inductive reactance, and capacitive reactance, is measured in ohms and may be substituted for resistance in Ohm’s law.

Answer 50

Impedance

Question 51

The capacitive reactance of capacitors connected in parallel is determined by ________________________________ .

Answer 51

calculating the total capacitance of the parallel-connected capacitors and using this value to calculate capacitive reactance

Question 52

Inductors and capacitors are electrical energy-storing devices that are used in AC and DC applications such as:

Answer 52

``` Timing circuits Surge protections Filtering circuits Fluorescent and HID lamp circuits 1Φ motors Motor control circuits And more! ```

Question 53

are small in size and have low capacitance ratings. Commonly range from pF to about 0.1 μF.

Answer 53

Mica capacitators

Question 54

Use wax paper or plastic film as the dielectric.

Answer 54

Paper capacitors

Question 55

Use ceramic as the dielectric. Can produce the same effect as a paper dielectric in less space.

Answer 55

Ceramic capacitors

Question 56

Use a paste as the dielectric, | provide more capacitance for their size than any other type of capacitors.

Answer 56

Electrolytic capacitors

Question 57

Normally use air or mylar as the dielectric and include movable and stationary metal plates.

Answer 57

Variable capacitors

Question 58

The charges on the plates of a capacitor reverse with each change in the applied voltage polarity when a capacitor is connected to an ______________. The plates are alternately charged and discharged.

Answer 58

AC power supply