Cheatwork-ECE.pdf - SOLID STATE PART 1 How many electrons are there in the fourth orbit of a copper atom A 1 B 2 C 3 D 4 View Answer Answer Option A

# Cheatwork-ECE.pdf - SOLID STATE PART 1 How many electrons...

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Unformatted text preview: SOLID STATE PART 1. How many electrons are there in the fourth orbit of a copper atom? A. 1 B. 2 C. 3 D. 4 View Answer: Answer: Option A Solution: 2. The maximum permissible number of electrons in the third orbit is A. 18 B. 8 C. 32 D. 2 View Answer: Answer: Option A Solution: 3. Varactor diodes are commonly used A. As voltage controlled capacitance B. As a constant current source C. As voltage multiplier D. As a constant voltage source View Answer: Answer: Option A Solution: 4. The reason why electrons are not pulled into the nucleus of an atom. A. Because of the centrifugal or outward force created by their orbital motion. B. Because of the force of attraction between them and the nucleus is weak. C. Because they are not being attracted by the positive nucleus. D. Because of the strong bonding between them that resists any force pulling them towards the nucleus. View Answer: Answer: Option A Solution: 5. The electrons in the largest orbit travel ________ than the electrons in the smaller orbits. A. More slowly B. Faster C. In the same velocity D. A little bit slower View Answer: Answer: Option A Solution: 6. A transistor configuration with the lowest current gain. A. Common base B. Common emitter C. Common collector D. Emitter-follower View Answer: Answer: Option A Solution: 7. A semiconductor in its purest form is called A. Pure semiconductor B. Doped semiconductor C. Intrinsic semiconductor D. Extrinsic semiconductor View Answer: Answer: Option C Solution: 8. Valence orbit is the other form for A. Outer orbit B. 3rd orbit C. 4th orbit D. 2nd orbit View Answer: Answer: Option A Solution: 9. K shell means A. First orbit B. 2nd orbit C. 3rd orbit D. 4th orbit View Answer: Answer: Option A Solution: 10. For either germanium or silicon diodes, the barrier potential decreases _______ for each Celsius degree rise. A. 1 mV B. 3 mV C. 4 mV D. 2 mv View Answer: Answer: Option D Solution: 11. A diode modeling circuit which considers the threshold voltage, average resistance and switch as the diode’s equivalent circuit. A. Ideal model B. Simplified model C. Piecewise linear model D. Real model View Answer: Answer: Option C Solution: 12. There are two mechanisms by which holes and electrons move through a silicon crystal. They are A. Covalent bond and recombination B. Diffusion and drift C. Free and charge particles D. Forward and reverse bias View Answer: Answer: Option B Solution: 13. A semiconductor is an element with a valence of A. Four B. Eight C. Two D. One View Answer: Answer: Option A Solution: 14. What orbit controls the electrical property of the atom? A. Valence orbit B. First orbit C. Fourth orbit D. M shell View Answer: Answer: Option A Solution: 15. ________ is a substance that contains atoms with several bands of electrons but with only one valence electron. A. Insulator B. Conductor C. Semiconductor D. Resistor View Answer: Answer: Option B Solution: 16. Pure silicon crystal atoms contain how may valence electrons as a result of covalent bonding? A. 1 B. 4 C. 8 D. 16 View Answer: Answer: Option C Solution: 17. The peak inverse voltage of a full wave center tapped rectifier circuit is equal to _______ of the input signal. A. Thrice the peak B. Twice the peak C. One half D. One third View Answer: Answer: Option B Solution: 18. Diffusion or storage capacitance is the term used to refer to A. The reverse bias capacitance of a diode B. The forward bias capacitance of a diode C. The breakdown capacitance of a zener diode D. The effective capacitance of the rectifier View Answer: Answer: Option B Solution: 19. What is considered as the key electrical conductivity? A. The number of electrons in the valence orbit B. The number of protons in the nucleus C. The number of neutrons in the nucleus D. The number of protons plus the number of electrons in the atom View Answer: Answer: Option A Solution: 20. Each atom in the silicon crystal has how many electrons in its valence orbit? A. 8 B. 32 C. 2 D. 4 View Answer: Answer: Option A Solution: 21. Lifetime is the amount of time between the creation and disappearance of a/an A. Free electron B. Proton C. Ion D. Neutron View Answer: Answer: Option A Solution: 22. A silicon crystal is an intrinsic semiconductor A. If every atom in the crystal is a silicon atom B. If majority of the atoms in crystal is a silicon atom C. If the crystal contains 14 silicon atoms D. If the crystal is undoped View Answer: Answer: Option A Solution: 23. At room temperature, a silicon crystal acts approximately like a/an A. Insulator B. Semiconductor C. Conductor D. Superconductor View Answer: Answer: Option A Solution: 24. An extrinsic semiconductor is a A. Doped semiconductor B. Pure semiconductor C. Good insulator D. Good conductor View Answer: Answer: Option A Solution: 25. What is associated with random motion due to thermal agitation in the movement of holes and electrons in a silicon crystal? A. Drift B. Diffusion C. Doping D. Recombination View Answer: Answer: Option B Solution: 26. The peak inverse voltage of a half wave rectifier circuit is approximately equal to the ________ of the input signal. A. Peak amplitude B. Frequency C. Voltage sinusoidal D. Current View Answer: Answer: Option A Solution: 27. Silicon that has been doped with a trivalent impurity is called a/an A. P-type semiconductor B. N-type semiconductor C. Intrinsic semiconductor D. Extrinsic semiconductor View Answer: Answer: Option A Solution: 28. Silicon that has been doped with a pentavalent impurity is called a/an A. N-type semiconductor B. P-type semiconductor C. Intrinsic semiconductor D. Extrinsic semiconductor View Answer: Answer: Option A Solution: 29. What is another name for a pn crystal A. Junction diode B. PN junction C. Diode D. Lattice View Answer: Answer: Option A Solution: 30. An acceptor atom is also called A. Pentavalent atom B. Trivalent atom C. Minority carrier D. Majority carrier View Answer: Answer: Option B Solution: 31. Which is a donor atom? A. Trivalent atom B. Aluminum C. Boron D. Pentavalent atom View Answer: Answer: Option D Solution: 32. In an n-type semiconductor, free electrons are called A. Minority carriers B. Valence electrons C. Majority carriers D. Charge carriers View Answer: Answer: Option C Solution: 33. in an n-type semiconductor, holes are called A. minority carriers B. majority carriers C. protons D. charge carriers View Answer: Answer: Option A Solution: 34. What is the barrier potential of germanium at 25˚C A. 0.7 V B. 0.3 V C. 0.5 V D. 0.4 V View Answer: Answer: Option B Solution: 35. The barrier potential for a silicon diode at 25˚C is approximately A. 0.4 V B. 0.3 V C. 0.7 V D. 0.5 V View Answer: Answer: Option C Solution: 36. Each pair of positive and negative ions at the junction is called a/an A. Anion B. Positron C. Cation D. Dipole View Answer: Answer: Option D Solution: 37. When temperature increases, barrier potential _________. A. Remains the same B. Decreases C. Increases D. Either increases or decreases depending on the semiconductor material used View Answer: Answer: Option B Solution: 38. Avalanche effects occurs at A. Higher reverse voltages B. Lower reverse voltages C. Higher forward voltages D. Lower forward voltages View Answer: Answer: Option A Solution: 39. The creation of free electrons through zener effect is also known as A. Avalanche emission B. Thermionic emission C. Low-field emission D. High-field emission View Answer: Answer: Option D Solution: 40. Zener effect only depends on the A. High-speed minority carriers B. High-speed majority carriers C. Intensity of the electric field D. Intensity of the magnetic field View Answer: Answer: Option C Solution: 41. What temperature is inside the diode, right at the junction of the p and n-type materials? A. Junction temperature B. Ambient temperature C. Internal temperature D. Absolute temperature View Answer: Answer: Option A Solution: 42. What is the input control parameter of a FET? A. Gate voltage B. Source voltage C. Drain voltage D. Gate current View Answer: Answer: Option A Solution: 43. One of the important diode parameters which gives the magnitude of current the diode candle without burning. A. Reverse saturation current B. Reverse current C. Forward current D. Forward breakdown current View Answer: Answer: Option C Solution: 44. The maximum reverse voltage that can be applied before current surges is called A. Reverse recovery time B. Maximum junction voltage C. Forward voltage D. Reverse breakdown voltage View Answer: Answer: Option D Solution: 45. What is the other name of Esaki diode? A. Diac B. Hot-carrier diode C. Shockley diode D. Tunnel diode View Answer: Answer: Option D Solution: 46. The most important application of Schottky diodes is in A. Digital computers B. Power supplies C. Amplifier circuits D. Voltage regulators View Answer: Answer: Option A Solution: 47. A diode is a nonlinear device because A. It produces a nonlinear graph B. Its current is not directly proportional to its voltage C. It has a built-in barrier potential D. It can rectify alternating current View Answer: Answer: Option B Solution: 48. The sum of the resistance of the p-region and the n-region is called A. Junction resistance B. Extrinsic resistance C. Intrinsic resistance D. Bulk resistance View Answer: Answer: Option D Solution: 49. What is the typical bulk resistance of rectifier diodes? A. Less than 1Ω B. Greater than 1Ω C. Equal to 1Ω D. It depends on the doping level View Answer: Answer: Option A Solution: 50. The reverse bias diode capacitance is termed as A. Transition region capacitance B. Diffusion capacitance C. Storage capacitance D. Reverse capacitance View Answer: Answer: Option A 51. The time taken by the diode to operate in the reversed condition from forward conduction. A. Maximum power time B. Reverse recovery time C. Lifetime D. Time allocation View Answer: Answer: Option B Solution: 52. Approximately, the atomic weight of germanium is A. 32 B. 28.09 C. 72.7 D. 16 View Answer: Answer: Option C Solution: 53. Atomic weight of silicon at 300 K is A. 28.09 B. 72.7 C. 5.32 D. 16 View Answer: Answer: Option A Solution: 54. An LED and phototransistor is equivalent to a/an A. Thermocouple B. FET C. Optocoupler D. Regulator View Answer: Answer: Option C Solution: 55. Optocoupler is otherwise known as A. Laser B. Photodiodes C. Optoisolator D. Photoconductive cell View Answer: Answer: Option C Solution: 56. When the emitter junction is forward biased while the collector junction is reverse biased, the transistor is at ________ region. A. Cut-off B. Saturation C. Active D. Breakdown View Answer: Answer: Option C Solution: 57. When both emitter and collector junction are forward biased, the transistor is said to be at _________ region. A. Active B. Cut-off C. Breakdown D. Saturation View Answer: Answer: Option D Solution: 58. An equivalent circuit of a diode in which it is represented as a switch in series with a barrier potential. A. First approximation B. Second approximation C. Third approximation D. Fourth approximation View Answer: Answer: Option B Solution: 59. Which of the following is the equivalent circuit for a diode for third approximation? A. A switch only B. A switch in series with a battery in series with a resistance C. A switch in series with battery D. A switch in series with a resistance View Answer: Answer: Option B Solution: 60. A silicon crystal is a/an ___________ of a semiconductor if every atom in the crystal is a silicon atom. A. Extrinsic B. Intrinsic C. P-type D. N-type View Answer: Answer: Option B Solution: 61. With pnp voltage divider bias, you must use A. Ground B. Negative power supplies C. Positive power supplies D. Resistors View Answer: Answer: Option B Solution: 62. Two pn silicon diodes are connected in series opposing. A 5 V voltage is impressed upon them. Find the voltage across each junction at room temperature when nVT= 0.052 V. A. 0.236 V, 3.2 V B. 4.764 V, 0.236 V C. 0.036 V, 4.964 V D. 3.21 V, 1.79 V View Answer: Answer: Option C Solution: 63. A half-wave signal has a period of A. 16.7 ms B. 8.3 ms C. 16.7 µs D. 8.3 µs View Answer: Answer: Option A Solution: 64. A full-wave signal has a period of A. 16.7 µs B. 8.3 µs C. 8.3 ms D. 16.7 ms View Answer: Answer: Option C Solution: 65. When doping increases, ________ of a semiconductor decreases. A. Impurity B. Conductivity C. Bulk resistance D. Minority carrier View Answer: Answer: Option C Solution: 66. Which of the following has the least noise level? A. FET B. BJT C. Triode D. Tetrode View Answer: Answer: Option A Solution: 67. Which of the following has the highest input impedance A. FET B. BJT C. MOSFET D. Crystal diode View Answer: Answer: Option C Solution: 68. The frequency of a half-wave signal is A. Twice the line frequency B. Equal to the line frequency C. One-half of the line frequency D. One-fourth the line frequency View Answer: Answer: Option B Solution: 69. For a full-wave rectifier, the output frequency A. Equals one-half the input frequency B. Equals the line frequency C. Equals two times the input D. Is three times the line frequency View Answer: Answer: Option C Solution: 70. The averaged dc voltage of a half wave rectifier circuit is _________ of the value of the peak input voltage. A. 63.6% B. 31.8% C. 4.8% D. 6.2% View Answer: Answer: Option B Solution: 71. The average dc voltage of a full wave rectifier circuit is __________ of the value of the peak input voltage. A. 31.8% B. 48.1% C. 63.6% D. 1% View Answer: Answer: Option C Solution: 72. Typical leakage current in a pn junction is in the order of A. µA B. mA C. nA D. pA View Answer: Answer: Option A Solution: 73. The resistance of a forward biased pn junction is in the order of A. Ω B. mΩ C. µΩ D. kΩ View Answer: Answer: Option A Solution: 74. The removal by electronic means of one extremity of an input waveform is called ________. A. Filtering B. Clamping C. Amplifying D. Clipping View Answer: Answer: Option D Solution: 75. Which of the choices below does not describe a clipper circuit? A. Limiter B. Amplitude selector C. Slicer D. Baseline stabilizer View Answer: Answer: Option D Solution: 76. The varactor diode is also called as A. Voltage-variable capacitance B. Varicap C. Epicap D. All of these View Answer: Answer: Option D Solution: 77. What diode has no depletion layer A. Varactor B. Varistor C. Schottky diode D. Shockley diode View Answer: Answer: Option D Solution: 78. Varistors are used for line filtering to eliminate spikes and dips and is also called A. Transient regulator B. Transient limiter C. Transient filter D. Transient suppressor View Answer: Answer: Option D Solution: 79. Defined as random motion of holes and free electrons due to thermal agitation A. Fission B. Fusion C. Diffusion D. Ionization View Answer: Answer: Option C Solution: 80. The temperature coefficient of resistance of a semiconductor is A. Positive B. Negative C. Zero D. Infinity View Answer: Answer: Option B Solution: 81. A large signal amplifier which is biased so that collector current flow continuously during the complete electrical cycle of the signal as well as when no signal is present A. Class A B. Class B C. Class AB D. Class C View Answer: Answer: Option A Solution: 82. A large signal amplifier which is biased so that current is non zero for less than one-half cycle. A. Class AB B. Class C C. Class A D. Class B View Answer: Answer: Option C Solution: 83. A class __________ amplifier stage operates with a small forward bias of the transistor so that some collector current flows at all times A. A B. B C. AB D. C View Answer: Answer: Option C Solution: 84. What factor is shown on a data sheet that tells how much you have to reduce the power of a device? A. Power factor B. Derating factor C. Reactive factor D. Reduction factor View Answer: Answer: Option B Solution: 85. The time it takes to turn off a forward-biased diode is called the A. Forward recovery time B. Reverse recovery time C. Recombination D. Turn-off time View Answer: Answer: Option B Solution: 86. A heavily doped semiconductor has A. High resistance B. No effect on the semiconductor characteristics C. More heat dissipation D. Low resistance View Answer: Answer: Option D Solution: 87. Gallium arsenide, aluminum arsenide and gallium phosphide are classified as A. Elementary semiconductor B. Secondary semiconductor C. Intrinsic material made by doping D. Insulators View Answer: Answer: Option B Solution: 88. A lightly doped semiconductor has A. Low resistance B. High resistance C. No effect on a semiconductor D. More heat dissipated behaviors View Answer: Answer: Option B Solution: 89. The property or ability of a material to support charge flow or electron flow A. Resistance B. Conductance C. Resistivity D. Permeance View Answer: Answer: Option B Solution: 90. What is also known as photodiffusion effect? A. Dember effect B. Skin effect C. Destriau effect D. Night effect View Answer: Answer: Option A Solution: 91. An effect that occurs within the entire bulk of a semiconductor material rather than in a localized region or junction A. Silicon effect B. Dember effect C. Bulk effect D. Destriau effect View Answer: Answer: Option C Solution: 92. The creation voltage in a conductor or semiconductor by illumination of one surface A. Dember effect B. Skin effect C. Destriau effect D. Night effect View Answer: Answer: Option A Solution: 93. What device uses a material catwhisker as its anode and is classified as a hot-carrier diode? A. PIN B. Point-contact diode C. Shockley diode D. Crystal diode View Answer: Answer: Option B Solution: 94. What is the typical operating current of an LED? A. 50 mA B. 10 mA C. 20 mA D. 5 mA View Answer: Answer: Option B Solution: 95. At absolute zero temperature, a semiconductor behaves as a/an A. Good conductor B. Superconductor C. Insulator D. Variable resistor View Answer: Answer: Option C Solution: 96. Avalanche breakdown in a semiconductor takes place A. When forward current exceeds a certain value B. When potential barrier is reduced to zero C. When reverse bias exceeds a certain value D. When forward bias exceeds a certain value View Answer: Answer: Option C Solution: 97. A cold-cathode glow-discharge diode having a copper anode and a large cathode of sodium or other material. A. Tunnel diode B. BARITT diode C. Anotron D. READ diode View Answer: Answer: Option C Solution: 98. A microwave diode in which the carriers that transverse the drift region are generated by minority carrier injection from a forward-biased junction instead of being extracted from the plasma of an avalanche region. A. IMPATT B. TRAPAT C. BARITT diode D. Esaki diode View Answer: Answer: Option C Solution: 99. What electronic circuit converts AC to DC where the DC output peak value can be greater than the AC input peak value? A. Voltage multiplier B. Rectifier C. Clamper D. Clipper View Answer: Answer: Option A Solution: 100. Which of the item below does not mean a VARACTOR diode? A. VOLTACAPS B. VARICAPS C. Voltage variable capacitors D. Variable resistance diode View Answer: Answer: Option D 101. What is the charge of the hole? A. Equal to that of a proton B. Equal to that of an electron C. Equal to that of a neutron D. Equal to zero View Answer: Answer: Option A Solution: 102. It is the current gain for the common-emitter configuration A. α B. β C. δ D. ρ View Answer: Answer: Option B Solution: 103. when a factor a junction transistor is 0.98,the factor would be equivalent to ________ value of transistor’s beta. A. 49 B. 60 C. 20 D. 38 View Answer: Answer: Option A Solution: 104. An emitter resistor is used for ________ in most amplifier circuits. A. Temperature stabilization B. Biasing a bipolar junction transistor C. Current limitation D. Voltage amplification View Answer: Answer: Option B Solution: 105. What line is drawn between the open-circuit current on a JFET characteristic curve? A. Operating point B. Load line C. Tangent line D. Quiescent point View Answer: Answer: Option B Soluti...
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