Description : Non-inverting amplifier circuits have _______ (a) Very high input impedance (b) very low input impedance (c) low output impedance (d) none of above
Last Answer : (a) Very high input impedance
Description : 27] In a transformer, the leakage flux of each winding is proportional to the current in that winding because A. Ohm's law applies to magnetic circuits B. Leakage paths do no saturate C. the two windings are electrically isolated D. mutual flux is confined to the core
Last Answer : B. Leakage path do not saturate
Description : Transistors are made from (a) Plastic (b) metals (c)insulators (d) doped semiconductors
Last Answer : d) doped semiconductors
Description : Silicon steel is used in electrical machines because it has?
Last Answer : Silicon steel is used in electrical machines because it has low hysteresis loss.
Description : Short-circuited stubs are preferred to open-circuited stubs because thelatter are a. more difficult to make an connect b. made of a transmission line with a different characteristic impedance c. liable to radiate
Last Answer : c. liable to radiate
Description : Current limited power supplies can prevent damage to A) Rectifier diodes and power transformers. B) Pass transistors C) Other circuits in the system D) All of the above.
Last Answer : D) All of the above.
Description : In digital ICs, Schottky transistors are preferred over normal transistors because of their (A) Lower Propagation delay. (B) Higher Propagation delay. (C) Lower Power dissipation. (D) Higher Power dissipation.
Last Answer : Ans: A Lower propagation delay as shottky transistors reduce the storage time delay by preventing the transistor from going deep into saturation.
Description : The electronic circuits which implement the various logic operations are called ________ (a) Logic gates (b) Boolean algebra (c) amplifier gain (d) logic functions
Last Answer : a) Logic gates
Description : For Tight Leakage Joints, Which Type Of Thread Is Best Suited?
Last Answer : NPT( National Pipe Threads)
Description : Semiconductor germanium and silicon are (a) Pentavalent (b) trivalent (c) divalent (d) tetravalent
Last Answer : (d) tetravalent
Description : Pure semiconductors silicon and germanium are a) Extrinsic b) Intrinsic c) Insulator d) Diodes
Last Answer : b) Intrinsic
Description : The resistivity of ..... decreases with the increase in temp. a. gold b. silver c. copper d. silicon
Last Answer : d. silicon
Last Answer : To limit the operating temperature an electrical machine should have proper current rating.
Description : The main electronic component used in first generation computers was A) Transistors B) Vacuum Tubes and Valves C) Integrated Circuits D) None of above
Last Answer : Answer : B
Description : Chief component of first generation computer was A) Transistors B) Vacuum Tubes and Valves C) Integrated Circuits D) None of above
Description : When troubleshooting a console circuit card suspected of being faulty, first check for proper voltages to the card and then _______________. A. test transistors or integrated circuits for gain and ... D. de-energize the card and check the printed circuit traces for continuity with an ohmmeter
Last Answer : Answer: C
Description : Chief component of first generation computer was a. Transistors b. Vacuum Tubes and Valves c. Integrated Circuits d. None of above
Last Answer : Vacuum Tubes and Valves
Last Answer : b. Vacuum Tubes and Valves
Description : Which of the following was used as circuitry for first generation of computers? (1) Vacuum tube (2) Transistors (3) Integrated circuits (4) Microprocessors
Last Answer : Vacuum tube
Description : Magnetising steel is normals difficult because (a) it corrodes easily (6) it has high permeability (c) it has high specific gravity (d) it has low permeability
Last Answer : (d) it has low permeability
Description : Since the characteristics of the device shown in figure 'A' of the illustration includes a stable voltage and low current while operating, it can be suitably used in _____________. EL-0065 A. oscillators ... . class A and B amplifiers C. generator rectifier and filtering supplies D. all of the above
Last Answer : Answer: A
Description : Thermistor with high negative temperature coefficient are very accurate for measuring low temperature especially near is a. 10 K b. 70K c. 200K d. 35K
Last Answer : c. 200K
Description : Silicon is used in which of the following? (1) Semiconductors (2) solar energy devices (3) transistors (4) All of these
Last Answer : (4) All of these Explanation: Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Description : A complete electronic circuit with transistors and other electronic components on a small silicon chip is called a(n) a) workstation b) CPU c) magnetic disk d) integrated circuit e) None of these
Last Answer : d) integrated circuit
Description : First generation computer systems used 1) Transistors 2) Vacuum tubes 3) Magnetic cores 4) Silicon chips
Last Answer : 2) Vacuum tubes
Description : Straight silicon steel (containing Si from 0.5 to 5%) because of their low hysteresis loss and high magnetic permeability are used for electrical appliances. Which of the following electrical ... /generators (B) Generators and small motors (C) Induction motors (D) High frequency transformers
Last Answer : (D) High frequency transformers
Description : Which is the most suitable power device for high frequency ( more 100 kHz) switching application? a) Power MOSFET b) BJT c) SCR d) UJT
Last Answer : Ans: Power MOSFET
Description : VLFwaves are used forsome type ofservices because a. of the low powers required b. the transmitting antennas are of convenient size c. they are very reliable d. the penetrate the ionosphere easily
Last Answer : c. they are very reliable
Description : The transfer function of a system is 10/(1+s) when operating as a unity feedback system, the steady state error to a step input will be a) 0 b) 1/11 c) 10 d) Infinity
Last Answer : Ans: 1/11
Description : Which of the listed classes of electrical insulation is suited for the highest operating temperature? A. Class 90 (O) B. Class 105 (A) C. Class 130 (B) D. Class 180 (H)
Last Answer : Answer: D
Description : In electronic circuits, what name is given to a frequency discriminating network designed to select or pass certain bands of frequencies with low attenuation and cause very high attenuation to other frequencies?
Last Answer : ANSWER: FILTER
Description : A power tiller is most suited for rotary cultivation because: A. It generates negative draft B. Its traction requirements are low C. It provides high degree of soil pulverization D. All of the above
Last Answer : D. All of the above
Description : Materials subjected to rapid reversal of magnetism should have (a) large area oiB-H loop (b) high permeability and low hysteresis loss (c) high co-ercivity and high retentivity (d) high co-ercivity and low density
Last Answer : (b) high permeability and low hysteresis loss
Description : Themaindisadvantage ofthe two-hole directional coupleris a. low directional coupling b. poor directivity c. high SWR d.narrowbandwidth
Last Answer : d.narrowbandwidth
Description : The operational amplifier is _______ (a) High gain amplifier (b) high power amplifier (c)high resistance amplifier (d)low resistance amplifier
Last Answer : a) High gain amplifier
Description : Process of conversion low voltage to high voltage is called _______ (a) Rectification (b)forward bias (c) reverse bias (d) amplification
Last Answer : (d) amplification
Description : The absorption ofradiowaves bythe atmosphere depends on a. their frequency b. their distance from the transmitter c. the polarization of the waves d. the polarization of the atmosphere
Last Answer : a. their frequency
Description : Arange ofmicrowave frequenciesmore easilypassed bythe atmospherethan are theothersis called a a.window b. critical frequency c. gyro frequency range d. resonance in the atmosphere
Last Answer : a.window
Description : Aship-to-ship communicationssystemisplagued byfading.The bestsolutionseemstobe useof a. a more directional antenna b. a broadband antenna c. frequency diversity d. space diversity
Last Answer : c. frequency diversity
Description : Distancesnearthe skip distance should beused forthe sky-wave propagation a. to avoid tilting b.topreventsky-wave andupper rayinterference c. to avoid the Faraday effect d. so as nor to exceed the critical frequency
Last Answer : b.topreventsky-wave andupper rayinterference
Description : Even though the main engine runs at varying speeds, how does the alternator maintain constant frequency?
Last Answer : By use of thyristor controlled frequency (rpm) converters.
Description : Why is it necessary that incoming alternator frequency is more than bus bar?
Last Answer : Prior to paralleling alternators together, the frequency of the incoming alternator is made slightly higher. This is to ensure that the incoming generator will take some of the bus load. If the incoming ... onto the bus. If this happens it is possible to cause other generators to trip off line.
Description : The minimum frequency required to eject electrons from a metallic surface is called a) Critical frequency b) Peak value of frequency c) Threshold frequency d)Photo frequency
Last Answer : c) Threshold frequency
Description : The minimum energy required to eject an electron from a metal surface is called a) Intensity b) Threshold frequency c) Work function d) Photo energy
Last Answer : c) Work function
Description : Can you guys explain the advantages of frequency converter against the star delta or soft starter?
Last Answer : ¬Soft starters A soft starter is, as you would expect, a device which ensures a soft starting of a motor. A softstarter has different characteristics to the other starting ... at rated current from zero to full speed. Frequency converters are becoming cheaper all the time.
Description : Diesel generators #1 and #2 are operating in parallel at near full load capacity. Diesel generator #1 suddenly trips out mechanically due to low lube oil pressure. The reverse power relay functions ... all nonvital circuits. D. Secure alarms, reset reverse power relay, and restart #1 engine.
Description : How do you test reverse power trip, high current trip, preferential trip?
Last Answer : Reverse power trip - refer answer for question 11. Also ask E/O. High current (over load trip) - Set your overload relay high current trip setting to say 75% of the rated current. Run the ... loads to overload the generator. Preferential trip will trip all the non-critical loads. Also ask E/O.
Description : A fuse is placed in series with the cireuit to protect against a. high power b. high voltage c. high current d. over heating
Last Answer : d. over heating
Description : The purpose of a heat sink, as frequently used with transistors, is to ____________. A. prevent excessive temperature rise B. compensate for excessive doping C. increase the reverse current D. decrease the forward current