Electronics 10% Flashcards
Two capacitors, each rated at 220 µF, are connected in parallel. The capacitance of the combination will be:
220µF
240µF
110µF
440µF
440µF
Two capacitors, each rated at 15 µF, are connected in series. The capacitance of the combination will be:
30µF
15µF
75µF
7.5µF
7.5µF
The fourth band of a four band resistor is marked in silver. This indicates a tolerance of:
25%
10%
20%
5%
10%
The third band of a four band resistor is marked in black. This indicates multiplier of:
10
1
100
1000
1
Two resistors, each measuring 15 Ω, are connected in series. The resistance of the combination will be:
30Ω
3Ω
15Ω
7.5Ω
30Ω
Two resistors, each measuring 220 Ω, are connected in parallel. The resistance of the combination will be:
220Ω
240Ω
110Ω
440Ω
110Ω
Resistor A is marked with the following colored bands: Red, Red, Red, Gold. The value of the resistor will be:
222 Ω 5%
2.2 kΩ 5%
22.2 kΩ 5%
333 Ω 5%
2.2 kΩ 5%
A battery of 24 V is connected across an unknown resistance. If a current of 0.5 A is supplied, which one of the following gives the value of the resistor?
6 Ω
48 Ω
12 Ω
24 Ω
48 Ω
An alternating current has a frequency of 2 kHz. Which one of the following gives the time for one complete cycle?
0.5 ms
1 ms
5 ms
2 ms
0.5 ms
The symbol used to denote charge in an electrical circuit is:
V
E
Q
C
Q
In a purely inductive circuit:
voltage leads current by 90°
voltage and current are in phase (0°)
current leads voltage by 90°
voltage lags current by 45°
voltage leads current by 90°
After which time constant can a capacitor be considered to be fully charged?
fifth
third
first
seventh
fifth
As a capacitor is being charged, current flowing into the capacitor will:
cannot tell
increase
remain the same
decrease
decrease
The electrical energy consumed by a coil is stored in the form of:
an electrical field
an electrostatic field
a magnetic field
a force field
a magnetic field
When a transformer secondary lead has been connected to a middle loop that is not an end connector, it is called a:
center-tapped secondary
multiple winding secondary
multiple-tapped secondary
single winding secondary
center-tapped secondary
Two inductors, each rated at 6.8 mH, are connected in parallel. The inductance of the combination will be:
16.8 mH
3.4 mH
6.8 mH
13.6 mH
3.4 mH
A loss-free transformer has 1200 primary turns and 300 secondary turns. If the primary winding is connected to a 200 V AC supply which one of the following gives the secondary voltage:
800 V
100 V
200 V
50 V
50 V
Two inductors, each rated at 22 mH, are connected in series. The inductance of the combination will be:
11 mH
22 mH
33 mH
44 mH
44 mH
In a purely capacitive circuit:
voltage leads current by 90°
voltage lags current by 45°
voltage and current are in phase (0°)
current leads voltage by 90°
current leads voltage by 90°
ICE
In an RLC circuit, Z represents:
Inductive reactance
Total impedence
Total resistance
Capacitive reactance
Total impedence
Under normal conditions a diode conducts current when it is:
reverse-biased
saturated
avalanched
forward-biased
forward-biased
The arrow on a schematic symbol for a diode points to the:
direction of electron flow
cathode
Anode
ground
cathode
An N-type semiconductor material:
is intrinsic.
has pentavalent impurity atoms added.
has trivalent impurity atoms added.
requires no doping.
has pentavalent impurity atoms added.
(known as doping)
An ideal diode presents a(n) ________ when reversed-biased and a(n) ________ when forward-biased.
short, short
open, open
short, open
open, short
open, short
The term bias in electronics usually means:
the value of DC voltages for the device to operate properly.
the status of the diode.
the condition of current through a PN junction.
the value of AC voltage in the signal.
the value of DC voltages for the device to operate properly.
The collector current in a bipolar junction transistor is 2 mA when the base current is 0.1 mA. Which one of the following gives the emitter current?
1.9 mA
20 mA
0.7 mA
2.1 mA
2.1 mA
In normal (conducting) operation, the voltage that will appear between the base and emitter of an NPN bipolar junction transistor will be approximately:
1.05 V
0.65 V
0.25 V
0.15 V
0.65 V
(Base/emitter voltage drop)
Which one of the following gives the relationship between the three currents flowing in an NPN bipolar junction transistor?
IC = IB + IE
IB = IE + IC
IE = IB + IC
IE = IB + IC
(Emitter current = Base current + Collector current)
The three terminals of a bipolar junction transistor are known as:
Emitter, base, collector
Source, gate, drain
Drain, base, collector
Emitter, gate, collector
Emitter, base, collector
In a semiconductor diode, the depletion region is removed when:
The diode is in its reverse non-conducting state
The cathode is more positive than the anode
The diode is in its forward conducting state
There is no potential difference between the anode and cathode
The diode is in its forward conducting state
The primary function of the bias circuit is to:
hold the circuit stable at the designed Q-point(operating point)
When a conductor interacts with a magnetic field, the induced current sets up a magnetic field that opposes the interaction. This is known as
Lenz’s Law
If a 3-input OR gate has eight input possibilities, how many of those possibilities will result in a HIGH output?
7
000=0
everything else would have a 1 so results in a 1 output
The output of an exclusive-OR gate is HIGH if:
-the inputs are unequal
-all inputs are LOW
-none are correct
-all inputs are HIGH
-the inputs are unequal
What does the small bubble on the output of the NAND gate logic symbol mean?
-The output is the
arithmetic sum of the
inputs
-The output is inverted
-The output is the absolute
value of the inputs
-None are correct
-The output is inverted
The output of a NOR gate is HIGH if:
-all inputs are HIGH
-any input is LOW
-all inputs are LOW
-any input is HIGH
-all inputs are LOW
The Boolean expression for a 3-input AND gate is:
X = A · B · C
X = A + B + C
X = A - B - C
X = A ⊕ B ⊕ C
X = A · B · C
A 2-input NAND gate output will be LOW if the inputs are:
00
10
01
11
11
00=1
10=1
01=1
11=0
Which of the following logical operations is represented by the + sign in Boolean algebra?
AND
OR
inversion
complementation
OR
The output of an OR gate with three inputs, A, B, and C, is LOW when:
A = 1, B = 1, C = 1
A = 0, B = 1, C = 1
A = 0, B = 0, C = 1
A = 0, B = 0, C = 0
A = 0, B = 0, C = 0
A device used to display one or more digital signals so that they can be compared to expected timing diagrams for the signals is a:
DMM
frequency counter
logic analyzer
spectrum analyzer
logic analyzer
The output of an AND gate with three inputs, A, B, and C, is HIGH when:
A = 1, B = 1, C = 0
A = 1, B = 0, C = 1
A = 1, B = 1, C = 1
A = 0, B = 0, C = 0
A = 1, B = 1, C = 1
All inputs High
What would the inputs have to be on a 3 input OR gate to get a low out?
A. All low
B. All high
C. 2 lows 1 high
D. 2 high 1 low
A. ALL LOW
Solve this binary equation. Answer in a decimal number form. 11011+1111=
A. 42
B. 54
C. 15
D. 101010
A. 42
A few capacitors are in parallel. Calculate the total capacitance. The capacitor values are1uF, 2uF, 3uF, and 4uF. The total capacitance is:
A. 10 uF
B. 5 uF
C. 1 uF
D. 01 uF
A. 10 uF
Use same method as resistors in series .
1µF + 2µF + 3µF + 4µF = 10µF
If a 4AH battery were replaced with a 2 AH with the same voltage rating, what would the result be?
A. Shorter run time.
B. Longer run time
C. Same run time
D. It would overheat the charging circuit
A. A SHORTER RUN TIME
A Nicad battery normally has:
A. 1.3 V per cell
B. 1.2 V per cell
C. 1.5 V per cell
D. 1.0 V per cell
B. 1.2 V per cell
Nickel-cadmium cells have a nominal cell potential of 1.2 volts (V).
10 to the minus 6 power is the prefix for which of the following?
A. Milli
B. Mega
C. Micro
D. Pico
C. MICRO
Which of the following is defined as volatile memory?
A. ROM
B. Flash
C. Stable
D. RAM
D. RAM
a. ROM non-volatile memory include read-only memory
b. Flash Flash memory is a non-volatile computer storage chip that can be electrically erasedand reprogrammed.
c. Stable
d. RAM The most widely used form of primary storage today is a volatile form of random access memory (RAM), meaning that when the computer is shut down, anything contained in RAM is lost.
Which of the following is the objective of a band-pass filter?
A. Allow a range of frequencies between an upper and lower cutoff point to pass through.
B. Allow a range of frequencies below a upper cutoff frequency to pass through.
C. Allow a range of frequencies above a lower cutoff frequency to pass through.
D. Allow a range of frequencies above an upper cutoff frequency and below a lower cutofffrequency to pass through.
A. Allow a range of frequencies between an upper and lower cutoff point to pass through.
In order for a basic power supply to operate correctly, which of the following is true?
A. The transformer must follow the regulator.
B. The rectifier must follow the filter.
C. The rectifier must follow the transformer.
D. The regulator must be before the filter.
C. The rectifier must follow the transformer.
Calculate the total inductance of two 40mH inductors in parallel.
A. 20 mH
B. 80 mH
C. 40 mH
D. 60mH
A. 20 mH
Calculate the total resistance of these resistors in parallel. 100 ohm, 3K ohm, 10K ohm.
A. 14100 ohms
B. 13100 ohms
C. 95 ohms
D. 100 ohms
C. 95 ohms
A few capacitors are in parallel. Calculate the total capacitance. The capacitor values are1uF, 2uF, 3uF, and 4uF. The total capacitance is:
A. 10 uF
B. 5 uF
C. 1 uF
D. 01 uF
A. 10 uF
Use same method as resistors in series .
1µF + 2µF + 3µF + 4µF = 10µF
Which of the following is best determined by using an oscilloscope?
A. The relationship between AC and DC in a circuit.
B. The amount of AC current in a circuit.
C. The amplitude of a DC signal.
D. The voltage dropped across a resistor.
A. The relationship between AC and DC in a circuit.
Which of the following occurs when batteries are connected in series?
A. The current capability increases.
B. The voltage provided will increase.
C. The smaller battery will explode.
D. The voltage provided will decrease.
b. The voltage provided will increase.
Connecting batteries in series increases voltage
Which of the following is the objective of a band-pass filter?
A. Allow a range of frequencies between an upper and lower cutoff point to pass through.
B. Allow a range of frequencies below a upper cutoff frequency to pass through.
C. Allow a range of frequencies above a lower cutoff frequency to pass through.
D. Allow a range of frequencies above an upper cutoff frequency and below a lower cutofffrequency to pass through.
A. Allow a range of frequencies between an upper and lower cutoff point to pass through.
The decimal number 255 is equivalent to which of the following Hexadecimal numbers?
A. AA
B. 100
C. FF
D. FA
C. FF
255/15=15 remainder 15
In Hex 15 is F, Therefore 255 in Hex is FF
Which of the following is the unit of measure for capacitance?
A. Henrys
B. Farads
C. Working volts
D. Coulombs
B. FARADS
Which of the following is the equivalent resistance of two 20 Ohm resistors in parallel in series with a 10 Ohm resistor?
A. 30 Ohms
B. 15 Ohms
C. 50 Ohms
D. 20 Ohm
D. 20 OHMS
Parallel: 1/((1/20)+(1/20)) = 10 Ohms
Add 10 Ohms from above with the 10 Ohm series resistor answer is 20 Ohms
A heating element uses 90 Watts of power and has a resistance of 1kΩ. Calculate the current through the heating element.
A. 0.09 milliamps
B. 0.300 milliamps
C. 300 milliamps
D. 9 milliamps
C. 300 milliamps
Power = I² X R B.
90W = I² X 1KΩ (90/1000) = I²
.09 = I²
.3 = I
Convert this number to decimal 4AF.
A. 1200
B. 1199
C. 1015
D. 1315
B. 1199
(416^2)+(A16^1)+(F*16^0)
=(4256)+(1016)+(15*1)
=1024+160+15=1199
An Oscilloscope reads 10 volts peak to peak. What is the RMS voltage?
A. 707 VRMS
B. 7.07 VRMS
C. 3.54 VRMS
D. 1.414 VRMS
C. 3.54 VRMS
Peak Voltage X .707 = RMS voltage
5V X .707 = 3.54 VRMS
A Triac is used to switch:
A. DC power
B. AC power
C. AC or DC power
D. FET gate current
B. AC power
the TRIAC a very convenient switch for AC circuits
A transformer has 1968 primary windings and 492 secondary windings (4:1) and the input current is 1 amp. Output current is?
A. 250 mA
B. 4 A
C. 500 mA
D. 2 A
B. 4 A
(Np/N/s) = (Ep/Es) = (Ip/Is)
(4/1) = (1/x) cross multiply 4=x
An isolation transformer is a transformer with:
a. primary and secondary windings physically separated
b. multiple secondary windings
c. an earth ground on the secondary windings
d. an earth ground on the primary winding
a. primary and secondary windings physically separated
Two coils are said to have mutual inductance when they are linked by:
a. a series wiring connection
b. a capacitor
c. an inductor
d. a common magnetic field
d. a common magnetic field
The unit of inductance is the:
a. ohm
b. rem
c. farad
d. Henry
d. Henry
A device to change one form of energy into another form of energy, eg. Mechanical to electrical, is called?
a. capacitor
b. transformer
c. transducer
d. transistor
c. transducer
If a technician measures a short or zero resistance across a capacitor on a circuit board and the reading doesn’t change, the technician should:
a. Measure the capacitor again
b. Verify continuity of the test leads
c. Replace the circuit board capacitor
d. Lift one leg of the capacitor and measure again
d. Lift one leg of the capacitor and measure again.
Just like measuring a resistor on a ckt board
- Which of the following best describes the sum of the voltage drops in a series resistor circuit?
a. Equals the applied voltage
b. Is less than the smallest voltage drop
c. Is usually more than the applied voltage
d. Is greater than the RMS value of all the voltage drops
a. Equals the applied voltage
- A battery has an open circuit voltage of 22 Volts connected to a load resistance of 200Ω, at 100ma. The internal resistance of the battery is ?
a. 2Ω
b. 20Ω
c. 220Ω
d. 2,200Ω
b. 20Ω
I | R
200 x .100 = 20V
22V-20V =2V
2V/100mA = 20hms
What is the inductive reactance of a 10mH coil at 400Hz
a. 1.26Ω
b. 2.51Ω
c. 12.6Ω
d. 25.1Ω
d. 25.1Ω
XL=2πfL
23.14400*.010=25.1
For screen film mammography, KVp is normally adjusted in increments of
a. 1kVp
b. 2kVp
c. 4kVp
d. 5kVp
a. 1kVp
If an ohmmeter test shows that a diode has an extremely high resistance In each direction, what is the condition of the diode
a. Open
b. Shorted
c. Conducting
d. Good
a. Open
The number FF in hex represents
a. An invalid number
b. 128 decimal
c. 255 decimal
d. 258 decimal
C. 255
F=15 in Hex, Hex is based on 16 base
FF= 15* 16(1) + 15 16(0)
1516=240
15* 16(0) =15
240+15=255
When using a DMM’s diode function test, a standard silicon PNP transistor, the collector to emitter should show
a. An open in one direction and a short in the other
b. An open in both directions
c. A short in both directions
d. A 0.7 volt reading
An open in both directions
What is the binary equivalent of the hex number B5??
a. 01011011
b. 10000111
c. 10110101
d. 11000011
C 10110101
B=1011, 5=0101
so binary of B5 is 10110101
Name the three elements of a MOSFET
a. Gate, source, and drain
b. Emitter, base, and collector
c. Base 1, base 2, and collector
d. Substrate, source, and collector
a. Gate, source, and drain
Which of the following transistor configurations has the lowest voltage gain?
a. Common Base
b. Common Emitter
c. Darlingtion pair
d. Common collector
a. Common Base
Voltage applied to E-B junction while output is taken from C-B junction which offers lowest voltage gain of 3 most common transistor configs ->Common Emitter, Common Base,
Common Collector.
If a transformer has a voltage step-down from 117 volts to 6 volts then the ratio of the transformer is equal to which of the following:
19.5:1
3:1
180:1
1:19.5
1:19.5
When a 60Hz sinusoidal voltage is applied to the input of a half-wave rectifier, the output frequency is:
30 Hz
0 Hz
60 Hz
120 Hz
60 Hz
If the current in a wire doubles, the induced magnetic field:
Remains the same
Quadruples
Doubles
Is reduced by half
Doubles
The usual operating region of transistors in digital circuits is:
Linear Region
Cutoff and Saturation Region
Active Region
Breakdown Region
Cutoff and Saturation Region
Avalanche in diode occurs at:
Breakdown voltage
Barrier potential
Knee voltage
Depletion layer
Breakdown voltage
The DC Current Gain of a Transistor is:
Ratio of Base Current to Emitter Current
Ratio of Collector Current to Base Current
Ratio of Base Current to Collector Current
Ratio of Emitter Current to Collector Current
Ratio of Collector Current to Base Current
The secondary of a current transformer must never be ____________ while energized.
Examined
Shortened
Grounded
Opened
Opened
Under normal conditions a diode conducts current when it is:
reverse-biased
saturated
avalanched
forward-biased
forward-biased
The wide end arrow on a schematic indicates the ________ of a diode.
anode
ground
direction of electron flow
Cathode
anode
An n-type semiconductor material:
is intrinsic.
has trivalent impurity atoms added.
has pentavalent impurity atoms added.
requires no doping.
has pentavalent impurity atoms added.
An ideal diode presents a(n) ________ when reversed-biased and a(n) ________ when forward- biased.
open, open
short, open
short, short
open, short
open, short
The term bias in electronics usually means:
the status of the diode.
the value of ac voltage in the signal.
the condition of current through a PN junction.
the value of dc voltages for the device to operate properly.
the value of dc voltages for the device to operate properly.
As a capacitor is being charged, current flowing into the capacitor will:
increase
remain the same
decrease
cannot tell
decrease
The electrical energy consumed by a coil is stored in the form of:
a magnetic field
a force field
an electrostatic field
an electrical field
a magnetic field
What type of device consists of a coil with a moveable iron core?
relay
armature
solenoid
reed switch
solenoid
In a purely inductive circuit:
voltage lags current by 90°
current leads voltage by 90°
voltage and current are in phase (0°)
voltage leads current by 90°
voltage leads current by 90°
Remember ELI
A TRIAC:
cannot be triggered with gate voltages
can be triggered by either a positive or a negative gate voltage
can trigger only on positive gate voltages
can trigger only on negative gate voltages
can be triggered by either a positive or a negative gate voltage
What does a hall effect sensor sense?
temperature
magnetic fields
moisture
pressure
magnetic fields
What causes the piezoelectric effect?
heat or dissimilar metals
a magnetic field
pressure on a crystal
water running on iron
pressure on a crystal
Junction Field Effect Transistors (JFET) contain how many diodes?
2
1
3
4
2
A varistor is:
a variable diode
a current-dependent resistor
a voltage-dependent resistor
a variable resistor
a voltage-dependent resistor
What circuit activity may shift a characteristic curve so that diode operating points are different?
higher power (heat)
higher resistance
lower current
lower voltag
higher power (heat)
When matching polarity connections have been made and the potential difference (PD) is above 0.7 V, a diode is considered to be:
not working
reverse biased
an open switch
forward biased
forward biased
A capacitor that produces an AC ground is called a(n):
ac open
coupling capacitor
bypass capacitor
dc open
bypass capacitor
Shunting the AC component away from the load is the task of a:
filter
regulator
transformer
rectifier
filter
A PN junction allows current flow when:
the p-type material is more positive than the n-type material
the n-type material is more positive than the p-type material
both the n-type and p-type materials have the same potential
there is no potential on the n-type or p-type materials
the p-type material is more positive than the n-type material
In a transistor, __________ .
IC = IE + IB
IE = IC + IB
IB = IC + IE
IE = IC - IB
IE = IC + IB
When a diode is forward biased, the voltage across it:
is inversely proportional to the current
is directly proportional to the source voltage
is directly proportional to the current
remains approximately the same
remains approximately the same
In a transistor, the base current is about _____ of the emitter current.
5%
20%
35%
25%
5%
At the base-emitter junctions of a transistor, one finds __________ .
a reverse bias
a wide depletion layer
none of the above
low resistance
low resistance
The most commonly used transistor arrangement is __________ arrangement.
Common collector
Common base
Common emitter
Cascade
Common emitter
The input impedance of a transistor is __________ .
Low
Very High
Almost Zero
High
Low
The output of an AND gate with three inputs, A, B, and C, is HIGH when ________.
A = 0, B = 0, C = 0
A = 1, B = 1, C = 1
A = 1, B = 1, C = 0
A = 1, B = 0, C = 1 .
A = 1, B = 1, C = 1
If a 3-input NOR gate has eight input possibilities, how many of those possibilities will result in a HIGH output?
7
2
8
1
1
If a signal passing through a gate is inhibited by sending a LOW into one of the inputs, and the output is HIGH, the gate is a(n):
AND
NAND
OR
NOR
NAND
A device used to display one or more digital signals so that they can be compared to expected timing diagrams for the signals is a:
DMM
logic analyzer
spectrum analyzer
frequency counter
frequency counter
The output of an OR gate with three inputs, A, B, and C, is LOW when ________.
A = 0, B = 1, C = 1
A = 1, B = 1, C = 1
A = 0, B = 0, C = 1
A = 0, B = 0, C = 0
A = 0, B = 0, C = 0
Which of the following logical operations is represented by the + sign in Boolean algebra?
OR
AND
complementation
inversion
OR
Output will be a LOW for any case when one or more inputs are zero for a(n):
OR gate
NOT gate
AND gate
NOR gate
AND gate
The Boolean expression for a 3-input AND gate is ________ .
= A · B · C
= A ⊕ B ⊕ C
= A + B + C
= A - B - C
= A · B · C
How many inputs of a four-input AND gate must be HIGH in order for the output of the logic gate to go HIGH?
all four inputs
any two of the inputs
any three of the inputs
any one of the inputs
all four inputs
The output of an exclusive-OR gate is HIGH if ________ .
all inputs are HIGH
all inputs are LOW
the inputs are unequal
none are correct
the inputs are unequal
If a 3-input OR gate has eight input possibilities, how many of those possibilities will result in a HIGH output?
8
1
2
7
7
A voltmeter is used:
In series with the circuit
To measure coulombs
To measure current
In parallel with the circuit
In parallel with the circuit
An atom’s atomic number is determined by the number of:
Neutrons minus protons
Protons
Electrons
Neutrons
Protons
Electricity may be generated by a wire?
That has neutral domains
Passing through a flux field
Wrapped as a coil
Carrying current
Passing through a flux field
A series circuit current:
Varies through each component
Remains the same through each component
Is subtracted by each component
Is the same as the individual resistances
Remains the same through each component
Most older types of paper capacitors have been replaced by which type of construction?
Electrolytic
Oxide casing
Waxed paper
Plastic film
Electrolytic
The component that produces power in an electromagnetic generator is called the:
Brush
Armature
Field winding
Commutator
Armature
As armature rotates, produces electrical power through electromagnetic induction.
In a power supply diagram, which block indicates a pulsating DC output?
Filter
Regulator
Transformer
Rectifier
Rectifier
A single transistor can be used to build which of the following digital logic gates?
OR gates
NAND gates
NOT gates
AND gates
NOT gates
What is the difference between binary coding and binary coded decimal?
Binary coding has a decimal format
Binary coding is pure binary
BCD has no decimal format
BCD is pure binary
Binary coding is pure binary
A data conversion system may be used to interface a digital computer system to
An analog output device
A digital input device
A digital output device
A digital printer
An analog output device
A Junction Field Effect Transistor (JFET)
has a low input resistance
is always forward-biased
is a current-controlled device
is a voltage-controlled device
is a voltage-controlled device
Which of the following memories uses a MOSFET and a capacitor as its memory cell?
DROM
SRAM
ROM
DRAM
DRAM
Which device would best aid in shorted track detection?
Current Tracer
Oscilloscope
Logic Pulser
Multimeter
Current Tracer
A basic S-R flip-flop can be constructed by cross-coupling which basic logic gates?
AND or NOR gates
XOR or XNOR gates
NOR or NAND gates
AND or OR gates
NOR or NAND gates
What is the peak value of a household appliance that uses a 120 VAC source?
112 V
170 V
230 V
115 V
170 V
What type of register would shift a complete binary number in one bit at a time and shift all the stored bits out one bit at a time?
SISO
PISO
PIPO
SIPO
SISO
With Ohm’s law, if voltage increases and resistance stays the same:
Current Increases
Current remains the same
Resistance Decreases
Power Decreases
Current Increases
The first step to getting output from a laser is to excite an active medium. What is this process called?
Raising
Priming
Exciting
Pumping
Pumping
What happens to current and resistance if the voltage doubles?
Current doubles and resistance remains the same.
Current doubles and resistance is halved.
Current remains the same and resistance doubles.
Current doubles and resistance doubles.
Current doubles and resistance remains the same.
What is the reactance value for a capacitor installed in a DC circuit?
Cannot tell
Infinite
Moderate
Zero
Infinite
Which of the following logical operations is represented by the + sign in Boolean algebra?
Inversion
Complementation
OR
AND
OR +
FYI: AND *
The color of light that you see is related to
The frequency of an electromagnetic wave
The amplitude of just a magnetic wave
The amplitude of just an electric wave
The frequency of just a magnetic wave
The frequency of an electromagnetic wave
Which digital system translates coded characters into a more intelligible form?
Counter
Decoder
Display
Encode
Decoder
What do we call atoms of the same element that have different neutron numbers?
Iions
Compounds
Isotope
Elements
Isotope
The inductive reactance of a transformer depends on
Electromotive Force
Magnetic Flux
Leakage Flux
Magnetomotive Force
Electromotive Force
A Digital to Analog converter is an application of the
Adjustable Bandwidth Circuit
Non Inverting Amplifier
Scaling adder
Voltage to Current Converter
Non Inverting Amplifier
How fast does a radio wave travel through a vacuum?
Its speed increases as the frequency increases
At the speed of light
At the speed of sound
Its speed is inversely proportional to its wavelength
At the speed of light
Plasma is:
-a gaseous medium
-a state of matter that is similar to gas, but the atomic particles are charged rather than neutral.
-a nearly incompressible fluid that conforms to the shape of its container but retains a constant volume independent of pressure.
-a medium dominated by helium
a state of matter that is similar to gas, but the atomic particles are charged rather than neutral.
The bridge used for measurement of inductance is?
Kelvin Double Bridge
Schering Bridge
Anderson Bridge
Wheatstone Bridge
Anderson Bridge
Current through the ionized gas in gas tube:
Usually assumes infinity
Usually fluctuates
Usually remains constant
Usually assumes zero value
Usually fluctuates
The frequency of audible sound for humans lies between:
15 KHz -> 1 MHz
1 MHz -> 15 MHz
None of these are correct
0.5Hz -> 20 KHz
0.5Hz -> 20 KHz
Which of the following is the fastest switching device?
JFET
MOSFET
Triode
BJT
MOSFET
What type of circuit is used in many FM receivers to convert signals coming from the IF amplifier to audio?
Mixer
Product detector
Phase inverter
Discriminator
Discriminator
What segments of the 7-segment LED display need to be energized to make the number 9?
a, b, d, f and g
b, c, d, e and g
a, b, e, f and g
a, b, c, f and g
a, b, c, f and g
The function of the starter for a DC motor is:
To increase field resistance
To limit the starting voltage
To limit the starting current
To reduce armature resistance
To limit the starting current
The speed of sound in air depends on:
Period of the wave
Air temperature
Frequency of the sound
Wavelength of the wave
Air temperature
In serial digital data communications, what must be added to the data?
Just parity bit
Only start and stop bits
Start, stop and parity bit for error detection and correction
Some error-detection and error-correction scheme
Start, stop and parity bit for error detection and correction
Which is not a transverse wave?
Waves in water
Sound
Vibration of a guitar string
X-Rays
Sound
Testing a good diode with an ohmmeter should indicate?
high resistance when reverse biased and low resistance when forward biased
The output of an OR gate with three inputs, A, B, and C, is LOW when ________
A = 0, B = 0, C = 0
The component that produces power in an electromagnetic generator is called the:
Armature
