Pretest

Question 1

True or False

Residential and commercial AC outlets are connected in series so that all connected devices receive the same voltage?

Answer 1

False

Question 2

Select which fuse would be the BEST choice for a 12Vdc, 2.5W camera?

a) 1/8A
b) 1/4A
c) 1/2A
d) 1A

Answer 2

c) 1/2 is best

Question 3

What voltages can be created using a 9V battery and a 1.5V battery in series?

a) 10.5Vdc
b) 7.5Vdc
c) 10.5Vdc and 7.5Vdc
d) 9Vdc and 1.5Vdc

Answer 3

c) 10.5Vdc and 7.5Vdc

Question 4

An oscilloscope measures_______ on its horizontal axis and ________ on its vertical axis?

a) Resistance, Capacitance
b) Current, Wattage
c) Time, Voltage
d) Voltage, Frequency

Answer 4

c) Time, Voltage

Question 5

Another way to express 123,000,000 mV would be:

a) 123,000 V
b) 123kV
c) .123MV
d) all the above

Answer 5

d) all the above

Question 6

If you place a 5k Ohm resistor in a circuit that will apply 120V across it, what size (wattage) resistor will you need?

a) 1/2 watt
b) 1 watt
c) 2 watt
d) 5 watt

Answer 6

d) 5 Watt

Question 7

Assuming equal lengths of wire, which gauge has the greatest amount of electrical resistance?

a) 6
b) 12
c) 18
d) 24

Answer 7

d) 24

Question 8

After installing BNC connectors on a 4 foot length of RG-59 cable, the Fluke 177 gives a reading of 0 Ohms from the center conductor to shield.

a) normal reading, cable is ready to use
b) normal reading, check center conductor end to end before using
c) abnormal reading, meter should show an open circuit (OL)
d) abnormal reading, meter should show 75 ohms

Answer 8

c) Abnormal reading, meter should show an open circuit (OL)

Question 9

Which of the following are true about series circuits?

A) as you add series resistance the current goes up
B) The voltage dropped across each resistor is always the same.
C) Current is the same through out the circuit.
D) The sum of all the voltage drops in a circuit will equal source voltage.

Answer 9

C and D

Question 10

The “difference of potential” is also known as?

Answer 10

Voltage

Question 11

True or False

A physically larger resistor can dissipate more heat than a small resistor made of the same material; therefore, the larger the resistor has a higher wattage rating.

Answer 11

True

Question 12

Frequency is measured in what units?

Answer 12

Hertz

Question 13

True or False

In a series circuit a larger resistor has a larger voltage drop.

Answer 13

True

Question 14

True or False

In a series circuit a larger resistance has a larger Power drop.

Answer 14

True

Question 15

True or False

In a series circuit, the total voltage, Vt, is the sum of all voltage drops.

Answer 15

True

Question 16

In Series, an open circuit, will have a total Current of ___________.

Answer 16

0 (Zero)

Question 17

True or False

In a Series, an open circuit will have zero voltage dropped across each good component.

Answer 17

True

Question 18

10mA equals how many Amps?

a) .001
b) .10
c) .01

Answer 18

c) .01 Amps

Question 19

How many kilovolts is 15V?

a) .15 kV
b) .015 kV
c) 1.5 kV

Answer 19

b) .015 kV

Question 20

How many micro Amps is .00025 Amps?

a) 250 uA
b) .25 mA
c) 25 nA

Answer 20

a) 250 uA

Question 21

When measuring resistance using the Fluke 177 DMM, the display shows ______ for a short circuit and _____ for an open circuit?

a) 0 ohms, 10 ohms
b) 5k ohms, OL
c) OL, 15 Mohms
d) 0 ohms, OL

Answer 21

d) 0 ohms, OL

Question 22

Which of the following is true of parallel circuits? (all that apply)

a) as you add parallel resistance the current total (I t goes up)
b) each resistance will have the same voltage drop
c) current is the same for all parallel branches regardless of resistance values
d) voltage drops across parallel branches vary, but added together equal source

Answer 22

a) as you add parallel resistance the current total (I t goes up)
b) each resistance will have the same voltage drop

Question 23

A common gauge wire used for an electrical outlet in a home is?

a) 14 gauge
b) 18 gauge
c) 22 gauge
d) 0 gauge

Answer 23

a) 14 gauge

Question 24

Using ohms law, if the supply voltage of a circuit is fixed and the resistance goes up, the current must:

a) go down
b) stay the same
c) go up
d) none of the above

Answer 24

a) go down

Question 25

True or False When wiring a simple "one way" AC switch in your house, the standard method is to attach the neutral wires to the switch.

Answer 25

False

Question 26

What size circuit breaker is needed for an electrical clothes dryer that consumes 5000 watts at 240 VAC? a) 15 amp b) 20 amp c) 30 amp d) 10 amp

Answer 26

c) 30 amp

Question 27

``` The schematic symbol below represents: | | ----- + -- ----- -- - | | ``` a) battery b) resistor c) capacitor d) cell

Answer 27

a) battery

Question 28

Four D cell batteries connected in series will give a potential difference of: a) 1.5v b) 3v c) 6v d) 10v

Answer 28

c) 6v

Question 29

True or False The most important specifications of a power supply are voltage and current.

Answer 29

True

Question 30

Audio is considered a(n): a) AC signal b) DC signal c) Fixed Frequency d) Positive DC voltage

Answer 30

a) AC signal

Question 31

True or False A 19 AWG (American Wire Gauge) conductor has a lower current carrying capacity than a 24 AWG conductor.

Answer 31

False

Question 32

Power in an electronic circuit, is expressed in what unit of measure? a) Watt b) Ohm c) Volt d) Amp

Answer 32

a) Watt

Question 33

True or False Series circuits only have one path for current to flow.

Answer 33

True

Question 34

True or False Current in a series circuit is the same throughout the circuit.

Answer 34

True

Question 35

Yes or No Does the positive terminal attract electrons as much as the negative terminal repels them?

Answer 35

Yes

Question 36

Yes or No Do all electrons have the same speed leaving and entering battery?

Answer 36

Yes

Question 37

Does a larger resister have a larger or smaller Voltage drop?

Answer 37

larger

Question 38

Does a larger resistance have a larger or smaller Power drop?

Answer 38

larger

Question 39

Yes or No In a series circuit, does the Total Voltage equal the sum of all Voltage drops?

Answer 39

Yes

Question 40

Select all that apply to a Series Open Circuit: a) Total Current equals zero b) 0V dropped across each good component c) source voltage across the open d) all the above

Answer 40

d) all the above

Question 41

Select all that applies in a Series Short Circuit: a) Current increases above normal b) Each good component drops more Voltage c) 0V dropped across the shorted component d) all the above

Answer 41

d) all the above

Question 42

Is a multimeter connected in series or parallel to measure current?

Answer 42

Series

Question 43

Does a multimeter in current mode have a very high or low resistance?

Answer 43

very low resistance

Question 44

True or False In a series circuit a defective component will have voltage drop that changes in the opposite direction when compared to all the good components.

Answer 44

True

Question 45

Yes or No In a series circuit, if one component is open, is there current in the circuit?

Answer 45

No

Question 46

How is a voltage measurement taken?

Answer 46

Voltage is difference of potential between two points in a circuit. Meter is placed across or in parallel with the circuit. Note: Meter is a high resistance load of 10M ohm connected to the circuit.

Question 47

How is a resistance measurement taken?

Answer 47

Meter provides the battery source for the measurement. Device to be measured must be isolated from the circuit, so disconnect one side or remove all together from the power source. Place meter leads across device to be measured.

Question 48

How do you take a current measurement?

Answer 48

Current is measured by opening the circuit and then restoring the open by placing the meter in series. Remember to move the red probe to the appropriate port and toggle the yellow button for DC on the Fluke DMM.

Question 49

How do you check the health of the Fluke fuses?

Answer 49

Set the selector to ohms position and using the red lead placed in the V/ohms port to probe the mA/A ports. A reading of OL equals a bad fuse.