Technicial License - Electrical Principals

Question 1

T5A05 (Pg. 4)
What is the electrical term for the force that causes electron flow?
A. Voltage <—-
B. Ampere-hours
C. Capacitance
D. Inductance

Answer 1

A. Voltage <—-
B. Ampere-hours
C. Capacitance
D. Inductance

Question 2

What causes energy to flow through a circuit? (Pg. 4)

Answer 2

VOLTAGE (V) wired to RESISTOR (R) causes CURRENT (I) (energy) to flow through CIRCUIT.

Question 3

Force that causes electrons to flow in a circuit.
Measured in volts;
V represents both the force and the units. (Pg. 4)

Answer 3

Voltage

Question 4

Electromotive Force or Electrical Potential;
Electromotive Force & Electric Potential measured in (Pg. 4)

Answer 4

Volts

Question 5

T5A03 (Pg. 5)
What is the name for the flow of electrons in an electric circuit?

Answer 5

A. Voltage
B. Resistance
C. Capacitance
D. CURRENT <—-

Question 6

T5A01 (Pg. 5)
Electrical current is measured in which of the following units?

Answer 6

A. Volts
B. Watts
C. Ohms
D. AMPERES <—-

Question 7

T5A09 (Pg. 6)
Which of the following describes alternating current?

Answer 7

A. Current that alternates between a positive direction and zero
B. Current that alternates between a negative direction and zero
C. CURRENT THAT ALTERNATES BETWEEN POSITIVE AND NEGATIVE DIRECTIONS <—-
D. All these answers are correct

Question 8

T5A12 (Pg. 6)
What describes the number of times per second that an alternating current makes a
complete cycle?

Answer 8

A. Pulse rate
B. Speed
C. Wavelength
D. FREQUENCY <—-

Question 9

T5A06 (Pg. 6)
What is the unit of frequency?

Answer 9

A. HERTZ <—-
B. Henry
C. Farad
D. Tesla

Question 10

T5A04 (Pg. 6)
What are the units of electrical resistance?

Answer 10

A. Siemens
B. Mhos
C. OHMS <—-
D. Coulombs

Question 11

T5A11 (Pg. 6)
What type of current flow is opposed by resistance?

Answer 11

A. Direct current
B. Alternating current
C. RF current
D. ALL THESE CHOICES ARE CORRECT <—-

Question 12

T5A07 (Pg.7)
Why are metals generally good conductors of electricity?

Answer 12

A. They have relatively high density
B. THEY HAVE MANY FREE ELECTRONS <—-
C. They have many free protons
D. All these choices are correct

Question 13

T5A08 (Pg. 7)
Which of the following is a good electrical insulator?

Answer 13

A. Copper
B. GLASS <—-
C. Aluminum
D. Mercury

Question 14

T5D02 (Pg. 8)
What formula is used to calculate voltage in a circuit?

Answer 14

A. E = I x R <——
B. E = I / R
C. E = I + R
D. E = I - R

Using simple algebra, you can derive the other two forms of this equation: R = E / I and I = E / R.
These two equations let you calculate the resistance in a circuit if you know the voltage and current or
the current in a circuit if you know the voltage and resistance.

Question 15

T5D03 (Pg. 8)
What formula is used to calculate resistance in a circuit?

Answer 15

A. R = E x I
B. R = E / I <—–
C. R = E + I
D. R = E – I

Question 16

T5D01 (Pg. 8)
What formula is used to calculate current in a circuit?

Answer 16

A. I = E  R
B. I = E / R <—-
C. I = E + R
D. I = E - R

Question 17

T5D04 (Pg. 8)
What is the resistance of a circuit in which a current of 3 amperes flows when
connected to 90 volts?

Answer 17

A. 3 ohms
B. 30 ohms <—–
C. 93 ohms
D. 270 ohms

Here’s how to calculate this answer: R = E / I = 90 volts / 3 amperes = 30 ohms.

Question 18

T5D05 (Pg. 9)
What is the resistance of a circuit for which the applied voltage is 12 volts and the
current flow is 1.5 amperes?

Answer 18

A. 18 ohms
B. 0.125 ohms
C. 8 ohms <——–
D. 13.5 ohms

R = E / I = 12 volts / 1.5 amperes = 8 ohms

Question 19

T5D06 (Pg. 9)
What is the resistance of a circuit that draws 4 amperes from a 12-volt source?

Answer 19

A. 3 ohms <—-
B. 16 ohms
C. 48 ohms
D. 8 ohms

R = E / I = 12 volts / 4 amperes = 3 ohms.

Question 20

T5D07 (Pg. 9)
What is the current in a circuit with an applied voltage of 120 volts and a resistance of
80 ohms?

Answer 20

A. 9600 amperes
B. 200 amperes
C. 0.667 amperes
D. 1.5 amperes <—-

I = E / R = 120 volts / 80 ohms = 1.5 amperes.

Question 21

T5D08 (Pg. 9)
What is the current through a 100-ohm resistor connected across 200 volts?

Answer 21

A. 20,000 amperes
B. 0.5 amperes
C. 2 amperes <—-
D. 100 amperes

I = E / R = 200 volts / 100 ohms = 2 amperes.

Question 22

T5D09 (Pg. 9)
What is the current through a 24-ohm resistor connected across 240 volts?

Answer 22

A. 24,000 amperes
B. 0.1 amperes
C. 10 amperes <—–
D. 216 amperes
I = E / R = 240 volts / 24 ohms = 10 amperes.

Question 23

T5D10 (Pg. 10)
What is the voltage across a 2-ohm resistor if a current of 0.5 amperes flows through
it?

Answer 23

A. 1 volt <—-
B. 0.25 volts
C. 2.5 volts
D. 1.5 volts

E = I × R = 0.5 amperes × 2 ohms = 1 volt.

Question 24

T5D11 (Pg. 10)
What is the voltage across a 10-ohm resistor if a current of 1 ampere flows through it?

Answer 24

A. 1 volt
B. 10 volts <—-
C. 11 volts
D. 9 volts
E = I × R = 1 amperes × 10 ohms = 10 volts.

Question 25

T5D12 (Pg. 10)
What is the voltage across a 10-ohm resistor if a current of 2 amperes flows through it?

Answer 25

A. 8 volts
B. 0.2 volts
C. 12 volts
D. 20 volts <—-

E = I × R = 2 amperes × 10 ohms = 20 volts.

Question 26

T5D13 (Pg. 11)
In which type of circuit is DC current the same through all components?

Answer 26

A. Series <—–
B. Parallel
C. Resonant
D. Branch

Question 27

T5D14 (Pg. 12)
In which type of circuit is voltage the same across all components?

Answer 27

A. Series
B. Parallel <—–
C. Resonant
D. Branch

Question 28

T5A10 (Pg. 13)
Which term describes the rate at which electrical energy is used?

Answer 28

A. Resistance
B. Current
C. Power <—-
D. Voltage

Question 29

T5A02 (Pg. 13)
Electrical power is measured in which of the following units?

Answer 29

A. Volts
B. Watts <—–
C. Watt-hours
D. Amperes

Question 30

T5C08 (Pg. 13)
What is the formula used to calculate electrical power (P) in a DC circuit?

Answer 30

A. P = E x I <——
B. P = E / I
C. P = E – I
D. P = E + I

Question 31

T5C09 (Pg. 13)
How much power is delivered by a voltage of 13.8 volts DC and a current of 10
amperes?

Answer 31

A. 138 watts <—–
B. 0.7 watts
C. 23.8 watts
D. 3.8 watts

The calculation for this question is P = E × I = 13.8 V × 10 A = 138 W.

Question 32

T5C10 (Pg. 13)
How much power is delivered by a voltage of 12 volts DC and a current of 2.5
amperes?

Answer 32

A. 4.8 watts
B. 30 watts <—–
C. 14.5 watts
D. 0.208 watts

The calculation for this question is P = E × I = 12 V × 2.5 A = 30 W

Question 33

T5C11 (Pg. 14)
How much current is required to deliver 120 watts at a voltage of 12 volts DC?

Answer 33

A. 0.1 amperes
B. 10 amperes
C. 12 amperes
D. 132 amperes

The calculation for this question is I = P / E = 120 W / 12 V = 10 A

Question 34

T5B01 (Pg. 15)
How many milliamperes is 1.5 amperes?

Answer 34

A. 15 milliamperes
B. 150 milliamperes
15
C. 1500 milliamperes <——
D. 15,000 milliamperes

To convert amperes to milliamperes, you multiply by 1,000.

Question 35

T5B02 (Pg. 16)
Which is equal to 1,500,000 hertz?

Answer 35

A. 1500 kHz <——
B. 1500 MHz
C. 15 GHz
D. 150 kHz

To convert from hertz (Hz) to kHz, you divide by 1,000.

Question 36

T5B03 (Pg. 16)
Which is equal to one kilovolt?

Answer 36

A. One one-thousandth of a volt
B. One hundred volts
C. One thousand volts <——
D. One million volts

Question 37

T5B04 (Pg. 16)
Which is equal to one microvolt?

Answer 37

A. One one-millionth of a volt <—-
B. One million volts
C. One thousand kilovolts
D. One one-thousandth of a volt

To convert from kilovolts to volts, you multiply by 1,000.

To convert from microvolts to volts, you divide by one million

Question 38

T5B05 (Pg. 16)
Which is equal to 500 milliwatts?

Answer 38

A. 0.02 watts
B. 0.5 watts <—-
C. 5 watts
D. 50 watts

To convert from milliwatts to watts, you divide by 1,000. 500 / 1000 = ½ or 0.5.

Question 39

T5B06 (Pg. 16)
Which is equal to 3000 milliamperes?

Answer 39

A. 0.003 amperes
B. 0.3 amperes
C. 3,000,000 amperes
D. 3 amperes <—-

There are a thousand milliamperes in an ampere, so to convert from milliamperes to amperes, you
divide by 1,000.

Question 40

T5C13 (Pg. 17)
16
What is the abbreviation for kilohertz?

Answer 40

A. KHZ
B. khz
C. khZ
D. kHz <—-

1 kHz is 1,000 Hz or 1,000 cycles per second. Note that the “H” in Hz is capitalized. 1,000,000 cycles
per second is 1,000 kHz, or 1 MHz.

Question 41

T5C07 (Pg. 17)
What is the abbreviation for megahertz?

Answer 41

A. MH
B. mh
C. Mhz
D. MHz <—-

Question 42

T5B07 (Pg. 17)
Which is equal to 3.525 MHz?

Answer 42

A. 0.003525 kHz
B. 35.25 kHz
C. 3525 kHz <—-
D. 3,525,000 kHz

Question 43

T5B12 (Pg. 17)
Which is equal to 28400 kHz?

Answer 43

A. 28.400 kHz
B. 2.800 MHz
C. 284.00 MHz
D. 28.400 MHz <—-

Question 44

T5B13 (Pg. 17)
Which is equal to 2425 MHz?

Answer 44

A. 0.002425 GHz
B. 24.25 GHz
C. 2.425 GHz <—-
D. 2425 GHz

To convert from MHz to kHz, you multiply by 1,000.

To convert from kHz to MHz, or to convert from MHz to GHz, you divide by 1,000.

Question 45

T5B08
Which is equal to 1,000,000 picofarads?

Answer 45

A. 0.001 microfarads
B. 1 microfarad
C. 1000 microfarads
D. 1,000,000,000 microfara