BASICEC4

Question 1

What does ELI ICE mean?

Answer 1

Voltage leads current in a purely inductive circuit.
Current leads voltage in a purely capacitive circuit.
V and I are in phase in purely resistive circuit.

Basic Electricity Ch4 p.2

Question 2

Quantities that have only magnitude are called ________ . Those that have magnitude and direction are called _________ .

Answer 2

scalars; vectors

Basic Electricity Ch4 p.3

Question 3

The length of a vector is proportional to the __________of the _______ it represents.

Answer 3

magnitude; quantity

Basic Electricity Ch4 p.4

Question 4

When adding and subtracting vectors, what is the result called?

Answer 4

resultant

Basic Electricity Ch4 p.5

Question 5

Two vectors that are 90 degrees apart can be added using what method?

Answer 5

Vector triangle method

Basic Electricity Ch4 p.10

Question 6

________ ______ are used to describe the time relationships between AC voltage and currents.

Answer 6

phase angles

Basic Electricity Ch4 p.14

Question 7

A waveform shows all of the instantaneous values of current or voltage throughout the complete _______ ______ _______ .

Answer 7

sine-wave cycle

Basic Electricity Ch4 p.20

Question 8

Component vectors in the same direction can be added ___________ .

Answer 8

arithmetically

Basic Electricity Ch4 p.24

Question 9

In an RL circuit, both resistance and inductive reactance oppose current flow. The combined effect is called …

Answer 9

impedance (Z)

Basic Electricity Ch4 p.26

Question 10

The values of Inductive reactance and R determine the angle of ______

Answer 10

Impedance (Z)

Basic Electricity Ch4 p.33

Question 11

In resistive circuits, all of the power delivered by the source is __________ by the ________ .

Answer 11

dissipated by the load

Basic Electricity Ch4 p.35

Question 12

Also known as merit rating, the ______ is the ratio of inductive reactance to resistance.

Answer 12

Q

Basic Electricity Ch4 p.36

Question 13

The ______ of a parallel RL circuit is always less than the resistance or inductive reactance of any of the branches.

Answer 13

impedance

Basic Electricity Ch4 p.48

Question 14

As the frequency ______ in a parallel RL circuit, the impedance comes closer and closer to the value of the resistance.

Answer 14

increases

Basic Electricity Ch4 p.50

Question 15

Current in a purely capacitive circuit ______ the voltage by 90 degrees.

Answer 15

leads

Basic Electricity Ch4 p.55

Question 16

In a parallel RC circuit, each branch voltage is ______ to the applied voltage.

Answer 16

equal

Basic Electricity Ch4 p.67

Question 17

The current in each branch of a parallel RC circuit is ______ of the current in the other branches.

Answer 17

independent

Basic Electricity Ch4 p.68

Question 18

______ ______ must be used to calculate impedance of a parallel RC circuit.

Answer 18

vector addition

Basic Electricity Ch4 p.72

Question 19

Frequency of applied voltage determines many characteristics of a parallel resistive capacitive circuit such as ______ _______ .

Answer 19

capacitive reactance
(which also affects impedance, line current, and phase angle)

Basic Electricity Ch4 p.73

Question 20

In a series LC circuit, one of the voltage drops, either E(L) or E(C) is always ______ than the applied voltage.

Answer 20

greater

Basic Electricity Ch4 p.80

Question 21

The magnitude of the current in series LC circuit is found using _______ ______.

Answer 21

Ohm’s Law

Basic Electricity Ch4 p.83

Question 22

The ______ is the total power delivered by the source.

Answer 22

apparent power

Basic Electricity Ch4 p.84

Question 23

The frequency at which the net reactance is zero, or where X(L) equals X(C), is known as the _______ ______.

Answer 23

resonant frequency

Basic Electricity Ch4 p.100

Question 24

Two identifying characteristics of resonance in a series LCR circuit are low ______ and large ______ .

Answer 24

low impedance and large current

For any given circuit, the impedance is at its minimum and the current is at its maximum resonance.

Basic Electricity Ch4 p.101

Question 25

The voltages across the branches of a parallel LC circuit are the same as the applied voltage. Because of this the voltage is used as the _______ _______ _______ ______.

Answer 25

zero-degree phase reference Basic Electricity Ch4 p.115

Question 26

The line current in a parallel LCR circuit is equal to ______ of the three branches.

Answer 26

the vector sum Basic Electricity Ch4 p.125

Question 27

The impedance of a parallel LCR circuit is found by finding the net reactance and combining it ______ with ______.

Answer 27

vectorially; resistance Basic Electricity Ch4 p.131

Question 28

If no line current flows, this means that the circuit has ________ ______ as far as the voltage source is concerned.

Answer 28

infinite impedance Basic Electricity Ch4 p.134

Question 29

At resonance, an ideal parallel resonant circuit has _______ line current and ______ impednace.

Answer 29

zero; infinite Basic Electricity Ch4 p.134

Question 30

At resonance, the ______ in a practical resonant circuit is ______ ______ with the applied voltage.

Answer 30

current; in phase Basic Electricity Ch4 p.138

Question 31

As used in electrical circuits, the term ______ means to offer large opposition to, or reject, voltages and currents of certain frequencies, and at the same time offer little opposition to, or pass, voltages and current of other frequencies.

Answer 31

filter Basic Electricity Ch4 p.149

Question 32

______ are often used to match the impedance of a source to that of a load.

Answer 32

transformers Basic Electricity Ch4 p.160