Electronics Final
To forward bias a silicone diode with a -1.6 V on the anode, you must apply a voltage of...
-2.3 V
Find VGS in Figure 17-2
-5V
Germanium diodes drop...
.3 V
If V=25V and R=50kOhm in Figure 3-1, the current equals
.5mA
Find VBE in Figure 17-1
.7V
What is the capacitance of a capacitor that drops 50V and stores 0.500uC of charge
0.01uF
Calculate the current in Figure 4-1
1.6mA
Pico is what relation to micro?
1/1,000,000th
A 50 kOhm potentiometer is connected across a 15 V source. If the voltage from the wiper to the lower end of the potentiometer is 3.2 V, what is the resistance of that lower part?
10.7 kOhm
IF a 1 uF capacitor and a 10k resistor are connected in series across 20V. Approximately how much voltage will the capacitor drop after charging for just one time constant?
12.6 V
(See Figure)What is the output voltage at the cutoff frequency?
15.6V
(See Figure) How much voltage does the resistor drop
20V
If a 330 Ohm resistor dissipates 2 W, its voltage drop equals
25.7 V
How long will it take for a 22uF capacitor to completely charge through a 47K resistor?
5.17s
What is the source voltage in a series resonant circuit if Vc =150V Vl=150V and Vr = 50V
50 V
If R1 = 4.7 kOhm, R2 = 3.3 kOhm and R3 = 1 kOhm in Figure 6-1, the total resistance equals
5467 Ohm
(See Figure) Calculate Vr2
6.84 Vp(not Vpp)
What is the total inductance if a 50mH inductor is connected in series with a 15mH inductor?
65mH
If a 22uF capacitor is connected to a 15V 400Hz source, its current equals
829mA
If 5 A and 3 A enter a junction from two seperate paths, how much current flows out of the junction?
8A
If a 4.7 kOhm resistor, a 3.3 kOhm resistor and a 5.43 kOhm resistor are connected in parallel across a 50 V source, what is the current through the 5.43 kOhm resistor?
9.21 mA
IF an RC integrator uses a 47uF capacitor, a 12K resistor and a square wave input with a frequency of 200 kHZ, its approximate output is
A near dc voltage of about half the square wave voltage.
Which is the correct formula for finding power?
All 3
A center tap transformer has a connection at the midpoint of the secondary winding resulting in
All of these
(See Figure) IF the output were taken across the resistor, the circuit would be known as a
High Pass Filter
(See Figure) Which statement describes the relationship of IL and IR?
IL lags IR
(See Figure) If the operating frequency increase, how does the phase angle change?
It decreases
(See Figure) IF the operating frequency increases, how does the current change
It increases
What is the purpose of the regulator?
Keep the dc output voltage constant as the load changes
(See Figure)The circuit in this figure is known as a ___
Low Pass Filter
(See Figure) The circuit is known as a
Low Pass filter
A capacitor blocks dc and passes ac
T
A step-down transformer could have a primary secondary turns ratio of 4:1
T
A zener diode is used as a constant voltage regulator.
T
As the frequency applied to an RC circuit increases, the impedance decreases
T
If a circuit's supply voltage is 15V and its resistance is 4700 ohms, its current is 3.19mA
T
If one branch of a parallel circuit shorts, the total resistance decreases
T
Most diodes are made from a semiconductor material called silicon.
T
Photodiodes will conduct more as the light intensity upon them increases.
T
The ideal amplifier has infinite gain, infinite input impedance, and zero output impedance.
T
The terminals on a three-terminal regulator are input voltage, output voltage and ground.
T
The voltage leads the current in an inductive circuit
T
To measure the current through a resistor, place the ammeter so the current must pass through the meter.
T
When connecting a large electrolytic capacitor to a circuit with a 100 Vdc source, place the negative end of the capacitor
Towards the negative side of the source
If the current in a circuit equals 0 A, it is likely that the...
circuit is open
A short in a series circuit results in
increased or maximum current flow.
(See Figure) If the frequency increase, the phase angle:
increases
IF the resistor shorts, the current
increases
If a resistor is rated at 1/2 W,
it can safely dissipate 1/2 of power.
For normal operation of a NPN transistor, the base must be...
positive with respect to the emitter.
The principal difference between a solenoid and a relay is that ...
solenoids do mechanical work, relays do electrical work.
If the voltage is suddenly switched off in Figure 3-1,
the current will suddenly drop to 0 A.
A full-wave rectifier requires...
two diodes and a center-tapped transformer.
IF a tuned tank circuit has a very narrow bandwidth, its Q is probably
very high
If the inputs are 4.1 V, -0.7 V, and 3.1 V in Figure 19-2(b), the output voltage equals...
-13 V
If Vin equals 8 V in Figure 19-1, VOut equals
-13V.
If the inputs are 8.4 V and 1.2 V in Figure 19-2(a), the output voltage equals
-9.6 V.
What is one time constant of a 4.7uF capacitor in series with a 22K resistor
103 ms
(See Figure) What is the primary current if Is = 40 mA and the turns ratio equals 4:1
10mA
If VIN = -3 V in figure 19-1, VOUT equals
13 V
If Vin equals 4 V in Figure 19-1, VOut equals
13V
If R = 47 kOhm and C= 0.02 uF in Figure 19-3, fCO equals...
169Hz
Add 21 mA and 8000uA and express the results in mA
29mA
What is the total supply voltage if 16 V and 12 V sources are wired in series opposing?
4V
(See Figure) What is the cutoff frequency?
85hz
What is the inductive reactance of a 150mH inductor operating at 10kHz
9420ohm
What change causes the circuit in Figure 19-2(b) to output the average of the three input voltages?
Change the feedback resistor to 3.3 kOhm.
When a diode is forward biased it is ...
Conducting current and similar to a closed switch
If R4 shorts in Figure 6-2, VR5
Decreases
.0047 Amps can be expressed in metric units as 47uA
F
A BJT has three elements: emitter, gate, and collector.
F
A sine wave's peak value is smaller than its RMS value
F
An ohmmeter can be used to accurately test the impedance of an RL circuit
F
Capacitance is the ability to store voltage
F
Electrolytic capacitors are ideal for AC applications
F
Electrons attract each other
F
If a 1/4 W resistor and a 1/2 W resistor are wired in series, they can safely dissipate 3/4 W.
F
If a DC voltage is input to a transformers primary, then an ac voltage is induced in its secondary,
F
If one branch of a parallel circuit opens, the total resistance decreases.
F
If three equal resistors are connected across 12 V in parallel, each resistor drops 4 V.
F
Most diodes are made from a semiconductor material called germanium.
F
Reverse breakdown usually occurs when a diode is forward biased by about .7 V.
F
The general characteristics of a common-emitter amplifier are low voltage gain, low current gain and very high power gain.
F
The total inductance of two parallel inductors equals the sums of their inductance values
F
When the input pulse width to an RC integrator is much less than 5pi, the output approaches the shape of the input
F
Identify the non-inverting amplifier in Figure 18-1.
Figure 18-1(b)
If an ohmmeter check of a diode indicates a high resistance in one direction and low resistance in the other, the diode is probably...
Good
If R2 shorts in Figure 4-1, the total circuit power....
Increases
The circuit in Figure 18-1(c) is known as the
Inverting amplifier
The device in Figure 17-2 is a
N-Channel JFET
Doping a semiconductor material with pentavalent impurities results in...
N-type material
With three capacitors in series, the current lags the voltage by
None of the above
The symbol for electric charge is
Q
What changes ac to pulsating dc?
Rectifier
The term reluctance in magnetic circuits is like the term ... in electrical circuits.
Resistance
To detect light, a photodiode requires
Reverse bias
In Figure 19-3, what will change the circuit into a high-pass filter?
Switching the positions of the resistor and capacitor.
A forward-biased silicon diode normally drops about .7 V.
T
A high pass filter will cause some phase shifting of the signal
T
A magnetic field around a conductor is a good indication that current if flowing.
T
A series RLC circuit can be configured for band-pass or band-stop filtering purposes.
T
A sine wave's frequency equals the reciprocal of the period
T
At resonance, Xc equals XL
T
The two types of BJTs are the NPN and PNP.
T
What will change the amplitude of ac voltage?
Transformer
In Figure 2-2, the voltage VGH is the same as
VR8
The basic difference between a fuse and a circuit breaker is that...
a circuit breaker is reusable
The circuit in Figure 18-1(a) is used as a
buffer amplifier
Beta is the ratio of
collector current to base current
IF an inductor has an ac current flowing through it, the magnetic field is:
constantly changing
If a BJT amplifier is operated as a switch that is off, this operating condition is known as....
cutoff
(See Figure) If the resistance decreases, the bandwidth
decreases
A typical op-amp has ... input impedance ... output impedance.
high, low
