When replacing a power transistor fitted with a heat sink in a circuit, a coating of silicone grease is applied between the transistor case and the heat sink. This is done to ____________. A. lubricate the transistor B. lubricate the heat sink C. aid in the removal of the heat sink D. provide maximum heat transfer

When replacing a power transistor fitted with a heat sink in a circuit, a coating of silicone grease is applied between the transistor case and the heat sink. This is done to ____________. A. lubricate the transistor B. lubricate the heat sink C. aid in the removal of the heat sink D. provide maximum heat transfer
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Answer: D
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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

Last Answer : Answer: D

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

Description : 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 ... damage to solid-state components C. dissipate stray magnetic currents D. act as a heat sink

Last Answer : Answer: D

Silicone resins, which are highly water repellent and has good heat resistance cannot be used (A) As room temperature adhesive (B) As grease & lubricant

Description : Silicone resins, which are highly water repellent and has good heat resistance cannot be used (A) As room temperature adhesive (B) As grease & lubricant

Last Answer : (A) As room temperature adhesive

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. C. Shift the 'Q' point to increase collector current. D. Increase the potential difference between the emitter and the base.

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.

Last Answer : Answer: B

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

Hand-portable phase sequence indicators should be used when ____________. A. installing a new synchroscope B. preparing to make the shore power connection C. replacing a defective solenoid D. all of the above

Description : Hand-portable phase sequence indicators should be used when ____________. A. installing a new synchroscope B. preparing to make the shore power connection C. replacing a defective solenoid D. all of the above

Last Answer : Answer: B

In a logic circuit the NOR and NAND gate functions ____________. A. must be accomplished with a common base transistor arrangement B. are available in diode form C. are exact opposites with the same NOR and NAND inputs D. have output conditions that are exact opposites to the output condition for OR and AND, respectively

Description : In a logic circuit the NOR and NAND gate functions ____________. A. must be accomplished with a common base transistor arrangement B. are available in diode form C. are exact opposites with the ... . have output conditions that are exact opposites to the output condition for OR and AND, respectively

Last Answer : Answer: D

To conduct an in-circuit test of a transistor, you should use a/an ____________. A. voltmeter or transistor tester B. impedance meter C. ohmmeter or transistor tester D. wattmeter

Description : To conduct an in-circuit test of a transistor, you should use a/an ____________. A. voltmeter or transistor tester B. impedance meter C. ohmmeter or transistor tester D. wattmeter

Last Answer : Answer: A

In order to check the performance of a transistor removed from its circuit, the instrument to be used should be a/an ____________. A. voltmeter or transistor tester B. impedance meter C. ohmmeter or transistor tester D. sensitive potentiometer

Description : In order to check the performance of a transistor removed from its circuit, the instrument to be used should be a/an ____________. A. voltmeter or transistor tester B. impedance meter C. ohmmeter or transistor tester D. sensitive potentiometer

Last Answer : Answer: C

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

Description : 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 ... oxidizing the leads to be soldered D. coating the leads to be soldered with a light oil film

Last Answer : Answer: B

The most inefficient method of voltage reduction, from the standpoint of power loss, even when placed in series with the load, is the use of a/an ____________. A. capacitor B. inductor C. resistor D. transistor

Description : The most inefficient method of voltage reduction, from the standpoint of power loss, even when placed in series with the load, is the use of a/an ____________. A. capacitor B. inductor C. resistor D. transistor

Last Answer : Answer: C

How to clean the frying pan of grease and carbon deposits without damaging the coating?

Description : How to clean the frying pan of grease and carbon deposits without damaging the coating?

Last Answer : How to clean the frying pan of grease and carbon deposits without damaging the coating? Even with the best housewife, over time, the pan will become covered with particles of burnt food, grease and ... the coating. I hope these simple tips will help you remove grease and deposits from your dishes.

Three factors responsible for the change in voltage as load is applied to an AC generator are: 1) the drop in resistance in the armature circuit, 2) the change in flux, and 3) the ____________. A. armature winding speed B. inductance load drop C. coil pitch factor D. armature reactance voltage drop

Description : Three factors responsible for the change in voltage as load is applied to an AC generator are: 1) the drop in resistance in the armature circuit, 2) the change in flux, and 3) the ____________. A. armature winding speed B. inductance load drop C. coil pitch factor D. armature reactance voltage drop

Last Answer : Answer: D

If the electricity represented by the wave form in 'B' were applied to the left side of the illustrated circuit, the output on the right side would be ____________. EL-0064 A. direct current with the top lead positive with repect to the lower lead B. direct current, half wave rectified with a ripple frequency of 60 hz C. direct current with the top lead negative with repect to the lower lead D. clipped to a value equal to the square root of 3 times the input voltage value

Description : If the electricity represented by the wave form in 'B' were applied to the left side of the illustrated circuit, the output on the right side would be ____________. EL-0064 A. direct current with the ... lower lead D. clipped to a value equal to the square root of 3 times the input voltage value

Last Answer : Answer: C

Under normal conditions, the speed of a two-speed squirrel cage induction motor is changed by varying the ____________. A. frequency of the applied voltage B. resistance in the rotor circuit C. number of field poles D. amplitude of the applied voltage

Description : Under normal conditions, the speed of a two-speed squirrel cage induction motor is changed by varying the ____________. A. frequency of the applied voltage B. resistance in the rotor circuit C. number of field poles D. amplitude of the applied voltage

Last Answer : Answer: C

In case of a pipe exit fitted with a nozzle, the (A) Conversion of kinetic head to pressure head is facilitated (B) Conversion of pressure head to kinetic head is facilitated (C) Power transmitted through the nozzle is maximum, when the head lost due to friction in the pipe is equal to one third of the total supply head (D) Both (B) and (C)

Description : In case of a pipe exit fitted with a nozzle, the (A) Conversion of kinetic head to pressure head is facilitated (B) Conversion of pressure head to kinetic head is facilitated (C) Power transmitted through the nozzle ... in the pipe is equal to one third of the total supply head (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

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

Last Answer : Answer: D

The purpose of a short circuit forcing module (short time trip) installed in a branch line is to provide ____________. A. high speed clearance of low impedance short circuits in the branch B. continuity of service on main bus under short circuit conditions in a branch C. isolation of short circuits by selective tripping of branch circuit breakers D. all of the above

Description : The purpose of a short circuit forcing module (short time trip) installed in a branch line is to provide ____________. A. high speed clearance of low impedance short circuits in the branch B. ... C. isolation of short circuits by selective tripping of branch circuit breakers D. all of the above

Last Answer : Answer: D

Why it is sometimes necessary to preheat the base material before welding? a) To remove oil and grease b) To remove moisture from inside the material c) To prevent the possible risk of cracking d) Not required if using cellulosic electrodes as these will provide enough heat

Description : Why it is sometimes necessary to preheat the base material before welding? a) To remove oil and grease b) To remove moisture from inside the material c) To prevent the possible risk of cracking d) Not required if using cellulosic electrodes as these will provide enough heat

Last Answer : c) To prevent the possible risk of cracking

Figure 'B' shown in the illustration represents a/an ____________. EL-0067 A. silicon controlled rectifier B. junction field effect transistor C. diac thyristor D. IG MOS field effect transistor

Description : Figure 'B' shown in the illustration represents a/an ____________. EL-0067 A. silicon controlled rectifier B. junction field effect transistor C. diac thyristor D. IG MOS field effect transistor

Last Answer : Answer: A

Figure 'A' of the diagram shown in the illustration represents a/an ____________. EL-0078 A. silicon controlled rectifier B. IG or MOS field effect transistor C. triac thyristor D. junction field effect transistor

Description : Figure 'A' of the diagram shown in the illustration represents a/an ____________. EL-0078 A. silicon controlled rectifier B. IG or MOS field effect transistor C. triac thyristor D. junction field effect transistor

Last Answer : Answer: B

Figure 'B' of the diagram shown in the illustration represents a/an ____________. EL-0065 A. silicon controlled rectifier B. junction field effect transistor C. diac thyristor D. IG or MOS field effect transistor

Description : Figure 'B' of the diagram shown in the illustration represents a/an ____________. EL-0065 A. silicon controlled rectifier B. junction field effect transistor C. diac thyristor D. IG or MOS field effect transistor

Last Answer : Answer: B

The symbol in figure 'A' shown in the illustration represents a ____________. EL-0065 A. diac B. field effect transistor C. silicon controlled rectifier D. unijunction transistor

Description : The symbol in figure 'A' shown in the illustration represents a ____________. EL-0065 A. diac B. field effect transistor C. silicon controlled rectifier D. unijunction transistor

Last Answer : Answer: D

Periodic testing of circuit breakers is necessary to assure that a correctly rated and properly installed unit _________________. A. can trip faster as it increases in age B. will continue to provide the original degree of protection C. does not exceed its interrupting capacity D. be able to withstand at least 125% of applied voltage

Description : Periodic testing of circuit breakers is necessary to assure that a correctly rated and properly installed unit _________________. A. can trip faster as it increases in age B. will continue to provide ... not exceed its interrupting capacity D. be able to withstand at least 125% of applied voltage

Last Answer : Answer: B

Which of the listed conditions will occur if dirt and grease are allowed to accumulate between the commutator segments of a motor? A. A partial short circuit. B. A dead short circuit. C. Misalignment of the motor shaft. D. Overspeeding of the motor.

Description : Which of the listed conditions will occur if dirt and grease are allowed to accumulate between the commutator segments of a motor? A. A partial short circuit. B. A dead short circuit. C. Misalignment of the motor shaft. D. Overspeeding of the motor.

Last Answer : Answer: A

What safety precaution must be taken before replacing a transistor?

Description : What safety precaution must be taken before replacing a transistor?

Last Answer : The power must be removed from the circuit.

What impedance relationship between the output of one circuit and the input of another circuit will provide the maximum power transfer?

Description : What impedance relationship between the output of one circuit and the input of another circuit will provide the maximum power transfer?

Last Answer : Equal impedance.

When the operating handle of a molded-case circuit breaker is in the mid-position, the circuit breaker is indicated as being ____________. A. in the 'closed' position B. in the 'opened' position C. tripped D. reset

Description : When the operating handle of a molded-case circuit breaker is in the mid-position, the circuit breaker is indicated as being ____________. A. in the 'closed' position B. in the 'opened' position C. tripped D. reset

Last Answer : Answer: C

When troubleshooting a console circuit card which is suspected of being faulty, the first step would be to _____. A. pull the card and measure the value of all resistors B. check for the correct value and polarity of all power connections to the card C. de-energize and pull the card to visually inspect for burned components D. check for continuity of circuit board traces and then the gain of each transistor

Description : When troubleshooting a console circuit card which is suspected of being faulty, the first step would be to _____. A. pull the card and measure the value of all resistors B. check for the ... for burned components D. check for continuity of circuit board traces and then the gain of each transistor

Last Answer : Answer: C

Removal of oil and grease from sewage, is known A. Screening B. Skimming C. Filtration D. None of these

Description : Removal of oil and grease from sewage, is known A. Screening B. Skimming C. Filtration D. None of these

Last Answer : ANS: B

Primary treatment of sewage consists of removal of A. Large suspended organic solids B. Oil and grease C. Sand and girt D. Floating materials

Description : Primary treatment of sewage consists of removal of A. Large suspended organic solids B. Oil and grease C. Sand and girt D. Floating materials

Last Answer : ANS: A

Ceramic coating material for furnace refractory, which increases itsemissivity and thus the radiation heat transfer rate in the furnace, comprises of (A) Graphite powder (B) Thoria (C) Zircon powder (D) Beryllium

Description : Ceramic coating material for furnace refractory, which increases itsemissivity and thus the radiation heat transfer rate in the furnace, comprises of (A) Graphite powder (B) Thoria (C) Zircon powder (D) Beryllium

Last Answer : (C) Zircon powder

Pick out the correct statement about the condensation. (A) Filmwise condensation gives a lower heat transfer rate than the dropwise condensation (B) Suitable coating or vapour additive is used to promote film wise condensation (C) If a condensing liquid does not wet the surface dropwise, even then condensation will take place on it (D) Reynolds number of condensing liquid is based on its mass flow rate

Description : Pick out the correct statement about the condensation. (A) Filmwise condensation gives a lower heat transfer rate than the dropwise condensation (B) Suitable coating or vapour additive is used to promote film ... place on it (D) Reynolds number of condensing liquid is based on its mass flow rate

Last Answer : (B) Suitable coating or vapour additive is used to promote film wise condensation

The rate at which heat is produced in a direct current circuit is equal to ____________. A. P divided by R B. I squared times R C. E divided by I D. I times R divided by T

Description : The rate at which heat is produced in a direct current circuit is equal to ____________. A. P divided by R B. I squared times R C. E divided by I D. I times R divided by T

Last Answer : Answer: B

If deck machinery is expected to be idle for an extended period of time you should____________. A. have electrical safety gloves available in case of electrical shock before running B. perform a 'high pot' test to determine the condition of the insulation C. water wash the motor and controller to remove any salt that may interfere with smooth operation D. check run at regular intervals to inusre correct operation and to renew the internal coating of lubrication

Description : If deck machinery is expected to be idle for an extended period of time you should____________. A. have electrical safety gloves available in case of electrical shock before running B. perform ... run at regular intervals to inusre correct operation and to renew the internal coating of lubrication

Last Answer : Answer: D

The removal of paint from electrical equipment, such as generators, should be cautiously undertaken because ____________. A. the mechanical shock of paint removal lessens the dielectric strength of the insulation B. the paint dust is composed of abrasive and semi-conducting materials which impair insulation C. paint dust buildup has a tendency to cause corrosion D. phase windings frequently become isolated from each other due to dust interference at the terminals

Description : The removal of paint from electrical equipment, such as generators, should be cautiously undertaken because ____________. A. the mechanical shock of paint removal lessens the dielectric strength ... phase windings frequently become isolated from each other due to dust interference at the terminals

Last Answer : Answer: B

When maintaining the circuit shown in the illustration, what dangers are associated with component 'C' should it become broken? EL-0081 A. Glass fragments may cut a person's skin. B. The contained mercury vapor is highly toxic. C. The inside coating of phosphor is highly poisonous. D. All of the above.

Description : When maintaining the circuit shown in the illustration, what dangers are associated with component 'C' should it become broken? EL-0081 A. Glass fragments may cut a person's skin. B. The contained mercury ... highly toxic. C. The inside coating of phosphor is highly poisonous. D. All of the above.

Last Answer : Answer: D

In addition to undercutting the mica, proper maintenance of a D.C. motor's commutator includes _______________. A. side-cutting the copper segments and insulating the slots B. coating the copper surface with light machine oil for the first four hours of operation C. baking the armature in an oven at a maximum of 95°C for not over 8 hours D. all of the above

Description : In addition to undercutting the mica, proper maintenance of a D.C. motor's commutator includes _______________. A. side-cutting the copper segments and insulating the slots B. coating the copper surface with light machine ... in an oven at a maximum of 95°C for not over 8 hours D. all of the above

Last Answer : Answer: A

Antireflection coating is helps in which case of the following? A. Minimizing the reflection of light from top surface B. To absorb and control the amount of light entering into the medium C. To allow maximum light to reflect from top surface D. To allow minimum light to enter into the medium

Description : Antireflection coating is helps in which case of the following? A. Minimizing the reflection of light from top surface B. To absorb and control the amount of light entering into the medium C. To allow maximum light to reflect from top surface D. To allow minimum light to enter into the medium

Last Answer : A. Minimizing the reflection of light from top surface

The speed of a series wound winch motor is controlled by ____________. A. varying the voltage applied to the motor B. the weight of the load on the cargo boom C. overcurrent protection devices in the motor D. a hydraulic speed-limiting governor

Description : The speed of a series wound winch motor is controlled by ____________. A. varying the voltage applied to the motor B. the weight of the load on the cargo boom C. overcurrent protection devices in the motor D. a hydraulic speed-limiting governor

Last Answer : Answer: A

____________ protocols provide end to end message transfer capability independent of the underlying network. A. Network layer B. Transport layer C. Application layer D. Link layer

Description : ____________ protocols provide end to end message transfer capability independent of the underlying network. A. Network layer B. Transport layer C. Application layer D. Link layer 

Last Answer : B. Transport layer 

Accidental grounds in a shipboard electrical system must be repaired as soon as possible as they will ____________. A. result in immediate power outages B. damage circuit breakers C. appear on the ground detection system D. damage insulation and may cause outages

Description : Accidental grounds in a shipboard electrical system must be repaired as soon as possible as they will ____________. A. result in immediate power outages B. damage circuit breakers C. appear on the ground detection system D. damage insulation and may cause outages

Last Answer : Answer: D

Undervoltage trips are frequently installed on switchboard circuit breakers to trip ____________. A. out generators in the event of severe arcing or sparking B. out generators when there is reversal of power in the main circuit C. the breaker if the generator overspeeds by 5%, but continues to run D. out generators when there is low voltage in the main circuit

Description : Undervoltage trips are frequently installed on switchboard circuit breakers to trip ____________. A. out generators in the event of severe arcing or sparking B. out generators when there is reversal of power ... , but continues to run D. out generators when there is low voltage in the main circuit

Last Answer : Answer: D

A wattmeter is used to determine ____________. A. the power being consumed by electrical equipment B. partial circuit resistance C. current flowing in a circuit D. voltage existing between two points in a circuit

Description : A wattmeter is used to determine ____________. A. the power being consumed by electrical equipment B. partial circuit resistance C. current flowing in a circuit D. voltage existing between two points in a circuit

Last Answer : Answer: A

In an emergency, the fastest way to interrupt power and stop the winch shown in the illustration is for the ____________. EL-0102 A. mate to open the disconnect switch at 'L1' and 'L2' B. winch operator to open the 'safe switch' at the 'master switch' C. engine room watch engineer to open the winch circuit breaker D. electrician to open the test link at the controller

Description : In an emergency, the fastest way to interrupt power and stop the winch shown in the illustration is for the ____________. EL-0102 A. mate to open the disconnect switch at 'L1' and 'L2' B. ... watch engineer to open the winch circuit breaker D. electrician to open the test link at the controller

Last Answer : Answer: B

Humming or buzzing of electric contacts is a symptom of ____________. A. low voltage on the operating coil B. power failure to the operating coil C. a control circuit ground D. a control circuit overload

Description : Humming or buzzing of electric contacts is a symptom of ____________. A. low voltage on the operating coil B. power failure to the operating coil C. a control circuit ground D. a control circuit overload

Last Answer : Answer: A

A transformer in an electric circuit serves to ____________. A. generate its own electrical power B. transform electrical energy into mechanical energy C. increase or decrease circuit voltage as required D. convert AC current to DC current

Description : A transformer in an electric circuit serves to ____________. A. generate its own electrical power B. transform electrical energy into mechanical energy C. increase or decrease circuit voltage as required D. convert AC current to DC current

Last Answer : Answer: C

An ohmmeter can be used to measure ____________. A. current flow in a circuit B. voltage between two points in a circuit C. circuit continuity D. power

Description : An ohmmeter can be used to measure ____________. A. current flow in a circuit B. voltage between two points in a circuit C. circuit continuity D. power

Last Answer : Answer: C