EASA module 4 Electronic Fundamentals mcq 8

An amplifier can provide both voltage gain and current gain when it is connected in the
a) common base configuration
Ans b) common emitter configuration
c) common collector configuration
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How do you increase voltage gain of an amplifier?
a) decrease base circuit bias
Ans b) decrease input resistance
c) increase input resistance
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In a resolver synchro the stator windings are electrically displaced by
Ans a) 90o
b) 120o
c) 180o
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A servo system may include a brake, an automatic trim system is one example where a brake is used. The brake is
a) applied during trimming to prevent oscillations about the demand position
Ans b) applied when trimming is complete to prevent stabilizer creep
c) applied during trimming to prevent servo runaway
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What gives the colour of an LED?
a) The plastic it is encased in
Ans b) The active element
c) The type of gas used inside it
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A germanium diode is used for
Ans a) rectification
b) voltage stabilization
c) modulation
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Why is a diode put in parallel with an LED?
Ans a) to protect it from AC
b) So it will work only above a certain voltage
c) So it will work only below a certain voltage
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When testing the forward bias of a diode with a multimeter
a) the positive lead of the ohmeter is placed on the cathode
Ans b) the positive lead of the ohmeter is placed on the anode
c) it does not matter which terminal the positive lead of the ohmeter is placed
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In an NPN transistor the P is the
a) collector
Ans b) base
c) emitter
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The output of a tachogenerator is
Ans a) proportional to speed of rotation
b) proportional to position
c) proportional to acceleration
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AC power is supplied to
a) torque receiver only
b) torque transmitter only
Ans c) both the torque receiver and torque transmitter
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This is a diagram of
a) a TRIAC
Ans b) an SCR
c) a Schottky diode
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How is a PCB protected after manufacture?
a) With non-conductive varnish
b) With wax
Ans c) By conformal coating
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A differential synchro
a) can only be used as a transmitter
b) can only be used as a receiver
Ans c) can be used as either a transmitter or a receiver
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Which of the following describes the characteristics of a Thyristor?
a) High voltage handling
Ans b) High current handling
c) High power handling
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A semiconductor doped with an element having a valency of 5 will produce
Ans a) an N type material
b) a P type material
c) either an N type or a P type depending on what type of semiconductor material is used
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What are the ideal characteristics of an Op Amp?
a) Infinite gain, infinite input Impedance and infinite output impedance
b) Low gain, infinite input Impedance and zero output impedance
Ans c) Infinite gain, infinite input Impedance and zero output impedance
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How is the amplifier in the diagram shown wired?
a) Common base
Ans b) Common emitter
c) Common collector
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What gate does the following Boolean expression represent
F = A.B.C
Ans a) AND
b) OR
c) NOT
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What gate does the following Boolean expression represent
F = A+B+C
a) NOT
b) NOR
Ans c) OR
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To decrease the voltage gain of a common emitter amplifier you would decrease the resistance in the
a) base circuit
Ans b) collector circuit
c) emitter circuit
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A resolver has
Ans a) 2 coils on the rotor and 2 coils on the stator
b) 3 coils on the rotor and 2 coils on the stator
c) 2 coils on the rotor and 3 coils on the stator
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The 'null' point on a control synchro is when the two rotors are
Ans a) at 90o to each other
b) parallel to each other
c) wired in series
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A FET when compared to a junction transistor is
a) low impedance
Ans b) high impedance
c) current operated
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What type of diode would be used to stop voltage spikes across a coil of a relay?
a) Gunn diode
b) Schottky diode
Ans c) Double acting diode
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A silicon diode, when compared to a germanium diode has
Ans a) a higher forward bias voltage
b) less forward bias voltage
c) the same forward bias voltage
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