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Your Answers

Correct

Q.1) A tachogenerator is usually used for:

A. position feedback

B. rate feedback (Your Answer)

C. angular feedback

Correct

Q.2) The _______ terminal of a MOSFET is insulated from the substrate.

A. source

B. gate (Your Answer)

C. drain

Correct

Q.3) Neutrons have ________ charge.

A. a positive

B. a negative

C. mass but no (Your Answer)

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Correct

Q.4) The arrow on the N-channel JFET points:

A. in (Your Answer)

B. out

C. arrow is not on gate

Correct

Q.5) Zener diodes are generaly operated:

A. as a rectifier

B. in their forward biase mode

C. in their reverse bias mode (Your Answer)

Incorrect

Q.6) The anode of a silicon diode is connected to a +5V DC supply and the cathode is connected to a

+4V DC supply. The diode is:

A. forward biased and not conducting (Your Answer)

B. reverse biased and not conducting (Answer)

C. forward biased and conducting

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Correct

Q.7) The process of adding impurities to pure semiconductor materials is called:

A. ionizing

B. bonding

C. doping (Your Answer)

Incorrect

Q.8) This MOSFET device requires a _______ condition to turn on.

A. positive bias (Your Answer)

B. negative bias

C. no bias (Answer)

Incorrect

Q.9) On a PNP transistor, if the base is made more positive than the emitter, the device will:

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A. snap into saturation (Your Answer)

B. turn on

C. turn off (Answer)

Correct

Q.10) The rotor of a torque synchro indicator is:

A. supplied with an excitation voltage (Your Answer)

B. connected in series with the stator coils

C. short-circuited

Correct

Q.11) A typical application for a zener diode is:

A. voltage stabilization (Your Answer)

B. power rectification

C. signal detection

Incorrect

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Q.12) This MOSFET device requires a _______ condition to turn on.

A. positive bias (Answer)

B. negative bias

C. no bias (Your Answer)

Incorrect

Q.13) Which FET device is most similar in operation to the BJT?

A. P-channel JFET (Your Answer)

B. depletion type MOSFET

C. enhancement type MOSFET (Answer)

Incorrect

Q.14) The forward voltage drop of a conducting silicon diode is approximately:

A. 0.2 V (Your Answer)

B. 0.6 V (Answer)

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C. 2 V

Incorrect

Q.15) The frequency of the ripple voltage present on the output of a bridge of a bridge rectifier fed

from a 400 Hz Ac supply will be:

A. 200 Hz (Answer)

B. 400 Hz

C. 800 Hz (Your Answer)

Correct

Q.16) The minority charge carrier in the N material is:

A. the electron

B. the hole (Your Answer)

C. subject to the impurity used

Incorrect

Q.17) A negative bias on the gate of a depletion type N-channel MOSFET will cause the current to:

A. increase (Your Answer)

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B. decrease (Answer)

C. become enhanced

Incorrect

Q.18) To increase the output of a servo amplifier, it is necessary to:

A. increase the tacho feedback

B. reduce the tacho feedback (Answer)

C. increase the position feedback (Your Answer)

Incorrect

Q.19) A thyristor has which of the following:

A. high resistance when switched on (Your Answer)

B. high resistance when switched off (Answer)

C. a positive temperature coefficient

Correct

Q.20) Atoms that contain 8 valence electrons make good:

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A. conductor materials

B. insulator materials (Your Answer)

C. semiconductor materials

Incorrect

Q.21) To reduce current flow through a P-channel JFET, the gate must be:

A. positive bias (Answer)

B. negative bias (Your Answer)

C. unbiased

Correct

Q.22) The N material in a diode forms the _____ of the diode.

A. anode

B. cathode (Your Answer)

C. depletion region

Correct

Q.23) In a speed control servo system, the purpose of the tachogenerator is

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A. to make the deflection proportional to servo demand

B. to make it run at constant speed (Your Answer)

C. to make the velocity proportional to servo demand

Incorrect

Q.24) Which transistor configuration amplifies the incoming signal without inverting it?

A. common base (Answer)

B. common emitter (Your Answer)

C. common collector

Correct

Q.25) When the base-emitter junction is forward biased, the base-collector junction is:

A. forward biased

B. reverse biased (Your Answer)

C. not affected

Correct

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Q.26) In the bridge rectifier arrangement shown, the DC output is taken from:

A. A and C (Your Answer)

B. A and B

C. B and D

Correct

Q.27) Generally, the ____ section is very narrow.

A. base (Your Answer)

B. emitter

C. collector

Correct

Q.28) A differential synchro has:

A. 3 phase stator, 3 phase rotor (Your Answer)

B. single phase stator, 3 phase rotor

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C. single phase stator, sinlge phase rotor

Correct

Q.29) The forward voltage drop of a conducting silicon diode is approximately:

A. 0.2 V

B. 0.6 V (Your Answer)

C. 2 V

Correct

Q.30) When testing a diode, if the positive meter lead is connected to the cathode, and the negative

meter lead is connected to the anode, the meter will read:

A. a forward bias condition

B. low resistance

C. open circuit (Your Answer)

Incorrect

Q.31) The logic symbol shown is for:

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A. NAND gate (Your Answer)

B. NOR gate (Answer)

C. OR gate

Correct

Q.32) Which one of the following relationships is correct for a BJT:

A. base current = collector current - emitter current

B. collector current = emitter current - base current (Your Answer)

C. emitter current = collector current - base current

Correct

Q.33) Which of the following semiconductors does not use a gate lead?

A. silicon-controlled switch

B. silicon-controlled rectifier

C. shockley diode (Your Answer)

Correct

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Q.34) Which transistor configuration inverts and amplifies the incoming signal?

A. common base

B. common emitter (Your Answer)

C. common collector

Incorrect

Q.35) What are the 2 energy bands associated with most solids?

A. valence...forbidden (Your Answer)

B. conduction...forbidden

C. conduction...valence (Answer)

Correct

Q.36) For current to flow through the JFET, the gate must be:

A. forward biased

B. reverse biased

C. unbiased (Your Answer)

Correct

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Q.37) The device shown is:

A. a thyristor

B. a PNP transistor

C. an NPN transistor (Your Answer)

Correct

Q.38) When a neutral atom loses a valence electron it becomes:

A. intrinsic material

B. positively charged (Your Answer)

C. negatively charged

Correct

Q.39) The device shown is used for:

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A. power control (Your Answer)

B. acting as a voltage reference

C. producing a visual indication

Correct

Q.40) A logic 1 is present at the output of a two-input NOR gate. Which one of the following is true?

A. both of its input must be at logic 1

B. both of its input must be at logic 0 (Your Answer)

C. one or more of its input must be at logic 1

Incorrect

Q.41) What are the two basic types of transistors?

A. FET & JFET

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B. NPN & PNP (Your Answer)

C. BJT & FET (Answer)

Correct

Q.42) Which of the leads shown in the figure is the emitter?

A. lead A

B. lead B

C. lead C (Your Answer)

Correct

Q.43) Atoms that contain an equal number of protons and electrons are called:

A. positive ions

B. negative ions

C. neutral atoms (Your Answer)

Incorrect

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Q.44) How are the pin numbers arranged in an operational amplifier IC?

A. counterclockwise from the dot (Answer)

B. clockwise from the dot (Your Answer)

C. left to right from the dot

Correct

Q.45) When the transistor is ON, the _______ current is always greater than the collector current.

A. base

B. emitter (Your Answer)

C. gate

Correct

Q.46) Trivalent impurties are added to intrinsic materials to manufacture:

A. N-type materials

B. P-type materials (Your Answer)

C. either N-type and P-type materials

Correct

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Q.47) A transistor operates with a base current of 45 mA and a collector current of 1.8 A. Which of the

following gives the current gain of the device when used in common-emitter configuration?

A. 40 (Your Answer)

B. 90

C. 225

Incorrect

Q.48) When a transistor is used in common-emitter mode:

A. the input is taken to the base and and output is taken from the collector (Answer)

B. the input is taken to collector and the output is taken from the emitter

C. the input is taken to the emitter and the output is taken from the collector (Your Answer)

Correct

Q.49) Which junction of the transistor must be forward biased for the device to turn ON?

A. emitter-collector

B. collector-base

C. emitter-base (Your Answer)

Correct

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Correct

Q.56) How do you increase the voltage gain of an amplifier?

A. increase input resistance

B. decrease base current bias

C. decrease input resistance (Your Answer)

Incorrect

Q.57) Which section of the BJT is generally doped the heaviest?

A. base

B. emitter (Answer)

C. collector (Your Answer)

Incorrect

Q.58) Which diode operates in a negative resistance region?

A. tunnel diode (Answer)

B. varactor diode

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C. zener diode (Your Answer)

Correct

Q.59) Which of the leads shown in the figure is the collector?

A. lead A (Your Answer)

B. lead B

C. lead C

Incorrect

Q.60) When a diode is forward biased, the majority charge carriers are pushed:

A. toward each other (Answer)

B. away from each other (Your Answer)

C. either direction

Correct

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Q.61) To turn off an SCR, you must:

A. apply a negative pulse to the gate terminal

B. reduce the positive bias at the gate

C. reduce the anode-to-cathode voltage to near zero (Your Answer)

Incorrect

Q.62) Which atomic bonding is commonly associated with insulator materials?

A. covalent (Your Answer)

B. metallic

C. ionic (Answer)

Incorrect

Q.63) A NOR gate with both inputs inverted becomes a:

A. NAND gate

B. AND gate (Your Answer)

C. OR gate (Answer)

Correct

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Q.64) A diode is considered forward biased when the:

A. anode is (+) and cathode is (-) (Your Answer)

B. anode is (-) and cathode is (+)

C. depletion region increases

Incorrect

Q.65) The area where the P and N materials are joined together is called the:

A. depletion region (Your Answer)

B. P-N junction (Answer)

C. enhancement region

Correct

Q.66) The maximum number of electrons that can exist in the valence shell is:

A. 3

B. 4

C. 8 (Your Answer)

Incorrect

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Q.67) The typical common-emitter current gain for a bipolar transistor is:

A. less than 10 (Your Answer)

B. between 10 and 40

C. more than 40 (Answer)

Correct

Q.68) Matter containing atoms with 3 or less valence electrons in their orbital paths are classified as:

A. conductors (Your Answer)

B. insulators

C. semiconductors

Incorrect

Q.69) Channel current in a JFET flows from:

A. source to drain (Your Answer)

B. drain to source

C. either direction (Answer)

Incorrect

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Q.70) The depletion region in a diode is void of:

A. majority charge carriers (Answer)

B. minority charge carriers

C. all electrons (Your Answer)