When a solid-state component of an electronic circuit is mounted to a metallic mass, the general purpose of that mass is to ____________. A. prevent vibration damage to delicate components B. prevent mechanical damage to solid-state components C. dissipate stray magnetic currents D. act as a heat sink

When a solid-state component of an electronic circuit is mounted to a metallic mass, the general purpose of that mass is to ____________. A. prevent vibration damage to delicate components B. prevent mechanical damage to solid-state components C. dissipate stray magnetic currents D. act as a heat sink
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Answer: D
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Related questions

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

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

Last Answer : Answer: A

When soldering a printed circuit board component, you should be careful to prevent damage by _________. A. quickly heating the joints, using a high wattage iron B. using the soldering iron tip sparingly C. using only acid cord solder D. applying mechanical pressure to the joints being soldered

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Last Answer : Answer: B

Two contributors of electronic console failures are heat and vibration. To combat some of their effects, preventive maintenance procedures should include ______________. A. systematic rotation of circuit cards with those from spares to allow component cooling B. periodic changing or cleaning of console ventilation and control room air conditioning filters C. weekly tightening of console foundation bolts and changing of the air in the control room D. all of the above

Description : Two contributors of electronic console failures are heat and vibration. To combat some of their effects, preventive maintenance procedures should include ______________. A. systematic rotation of circuit cards with those ... bolts and changing of the air in the control room D. all of the above

Last Answer : Answer: B

When troubleshooting electronic equipment, you should use a high impedance multimeter ________________. A. to prevent excess current flow through the meter that would damage it B. for AC measurements only and a low resistance meter for DC measurements C. whenever a low impedance meter is not available, regardless of the components being tested D. so as not to load down the circuit and obtain erroneous voltage readings

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Last Answer : Answer: D

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Description : Which of the following statements is true concerning the cleaning of electrical contacts? A. Compressed air should be used to blow out metallic dust. B. Magnetic brushes should be used to remove ... contact resistance. D. Delicate parts should be cleaned with a brush and an approved safety solvent.

Last Answer : Answer: D

If a delicate component must be soldered into a circuit, the component may be protected from the heat of the soldering process by _____________. A. operating the soldering gun not more than 60 seconds at a time B. using a thermal shunt C. pre-oxidizing the leads to be soldered D. coating the leads to be soldered with a light oil film

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The purpose of the capacitor within component 'B' of the circuit shown in the illustration is to ____________. EL-0081 A. prolong the life of the component's contacts B. discharge the neon within the envelope C. counteract the inductive reactance in the circuit D. store power to operate the circuit should 'D' open

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Last Answer : Answer: A

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Last Answer : Answer: D

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Last Answer : Answer: C

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Last Answer : Answer: D

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Description : A solid-state circuit is inoperative; the FIRST action that should be taken is to ____________. A. wiggle all the components to check for loose connections B. check all the resistors C. change all transistors D. check the DC supply voltage

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Last Answer : Answer: B

A shading coil used in an AC magnetic controller, functions to _____________. A. reduce vibration and noise in the contactor B. prevent flux buildup in the operating coil C. eliminate arcing when the contacts close D. energize the operating coil and 'pull in' the contacts

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Description : Which of the following actions can be carried out in order to prevent thermal runaway in a transistor? A. Increase the current through the collector-base junction. B. Install a heat sink. ... point to increase collector current. D. Increase the potential difference between the emitter and the base.

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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

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When replacing component 'B' of the circuit shown in the illustration, it is important to know that ____________. EL-0081 A. it is polarity sensitive and must be inserted as indicated on its base B. there is a danger of phosphor poisoning should 'B''s bulb break C. component 'D' must be closed during the replacement to provide the capacitor's initial charge D. it must match the circuit voltage and component 'C' wattage

Description : When replacing component 'B' of the circuit shown in the illustration, it is important to know that ____________. EL-0081 A. it is polarity sensitive and must be inserted as indicated on its ... provide the capacitor's initial charge D. it must match the circuit voltage and component 'C' wattage

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When changing out component 'B' of the circuit shown in the illustration, it is important to know that ____________. EL-0081 A. it is polarity sensitive and must be inserted as indicated on its base B. there is a danger of phosphor poisoning should 'B''s bulb break C. component 'D' must be closed during the replacement to provide the capacitor's initial charge D. it must match the circuit voltage and component 'C' wattage

Description : When changing out component 'B' of the circuit shown in the illustration, it is important to know that ____________. EL-0081 A. it is polarity sensitive and must be inserted as indicated on its ... provide the capacitor's initial charge D. it must match the circuit voltage and component 'C' wattage

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During the start-up of the circuit shown in the illustration, it is noted that the ends of component 'C' remain lighted but the tube does not illuminate. The cause of this problem is ____________. EL-0081 A. component 'A' is open B. component 'D' is closed C. component 'C' is the wrong wattage D. component 'B' contacts are stuck closed

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Description : From the following, which one is a type of vibration measuring instrument? A Mechanical B Electrical C Magnetic D All of the above

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Description : From the following, which one is a type of vibration measuring instrument?(A) Mechanical (B) Electrical (C) Magnetic (D) All of the above

Last Answer : (D) All of the above

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Description : When troubleshooting electronic equipment, the FIRST step to be taken before testing the circuit voltage is to _________. A. set the meter to the lowest range B. check the voltage supply from the power source C. remove the suspected component D. check the current flow through the circuit

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If overloading a DC machine becomes necessary in an emergency, you should ____________. A. cool the machine with portable blowers and fans B. hold thermal overload relays open with blocks of wood C. inject small amounts of CO2 into the windings for cooling D. increase the residual magnetism value of windings to reduce eddy currents

Description : If overloading a DC machine becomes necessary in an emergency, you should ____________. A. cool the machine with portable blowers and fans B. hold thermal overload relays open with blocks of ... the windings for cooling D. increase the residual magnetism value of windings to reduce eddy currents

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If coil 'R1-R2' on the transmitter in figure 'A' shown in the illustration is turned 30 degrees clockwise, corresponding coil 'R1-R2' on the receiver should ____________. EL-0092 A. make coils 'S1-S2-S3' turn faster because of induced currents B. ring at the receiving station until the turning stops C. receive a higher voltage depending on the turns ratio D. align itself to the same position if free to move

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In order to prevent the winch shown in the illustration from turning while troubleshooting the controller circuit, _________________. EL-0102 A. set the dynamic brake by clamping contact 'DB' closed B. set the mechanical brake by the jackscrew provided C. disconnect the brake solenoid at 'B1' and 'B2' D. open the test link preventing current flow to the armature

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Last Answer : Answer: D

A reverse-current relay will prevent AC generator motorization by ____________. A. automatically redirecting the load B. automatically speeding up the prime mover C. tripping the panel board main switch D. tripping the generator circuit breaker

Description : A reverse-current relay will prevent AC generator motorization by ____________. A. automatically redirecting the load B. automatically speeding up the prime mover C. tripping the panel board main switch D. tripping the generator circuit breaker

Last Answer : Answer: D

As shown in the illustration, a 'pitch cutback' feature is incorporated in the system. This circuit reduces pitch amount to prevent engine overload when it senses ____________. EL-0095 A. pitch error of any magnitude B. wrong direction of the 'pitch servo' C. excessive propeller speed or fuel to either engine D. only one engine on the line

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There are n rotors mounted on the shaft and when subjected to torsional vibration there will be A. N nodes B. (N-1) nodes C. (N+1) nodesD. Any number of nodes

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