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ATT TEST 4 NEWEST TEST 2025 | ALL QUESTIONS
AND CORRECT ANSWERS | GRADED A+ | LATEST
TEST | VERIFIED ANSWERS
In an AC generator the output voltage across the load in the external circuit reverses polarity with every what rotation? ---------CORRECT ANSWER----- ------------180 degree What principle of magnetism do motors operate on? ---------CORRECT ANSWER-----------------Attraction and repulsion What principle of magnetism do generators operate on? ---------CORRECT ANSWER-----------------Producing voltage; passing a conductor through a magnetic field What devices are affected by a shorted stator winding on a transmitter? ---- -----CORRECT ANSWER-----------------All of them What device reduces noise and redirects the air stream so it will not cause any injuries? ---------CORRECT ANSWER-----------------The muffler What does the fluid provide to the rotary pump in a hydraulic system? ------- --CORRECT ANSWER-----------------Lubrication and cooling
What is the major difference between the torque synchro system and the control synchro system? ---------CORRECT ANSWER----------------- Control=dry signal= synchro system What is the relationship between distance and time when solving for velocity? ---------CORRECT ANSWER-----------------🔺D / 🔺T Worn packing in a pump causes ---------CORRECT ANSWER----------------- Leaks What principle of magnetism allows a generator to power its own stator windings and still generate an output voltage? ---------CORRECT ANSWER-----------------Retentivity How does an incremental motor operate? ---------CORRECT ANSWER------ -----------Specific differences for each What type of positive displacement pump is used in most hydraulic systems? ---------CORRECT ANSWER-----------------Rotary What are the basic components of a synchro? ---------CORRECT ANSWER-----------------Stator and rotor Which device in the control synchro system performs the same function as the torque transmitter? ---------CORRECT ANSWER-----------------Control transmitter
(PID) What is the condition which indicates the values of a circuit have settled and tend to remain constant? ---------CORRECT ANSWER------------- ----Steady state (PID) What is the optimum operating parameter or a reference to which an operator adjusts the process of optimum operation? ---------CORRECT ANSWER-----------------Set point What is the sequence for energizing the stator shoe a clockwise pattern? -- -------CORRECT ANSWER-----------------A,B,A w/ hat,B w/ hat The piston compressor is one type of ---------CORRECT ANSWER------------ -----Displacement compressor What term is used to describe the highest PPS a stepper motor can use? -- -------CORRECT ANSWER-----------------Slew Rate (Sr) What is the purpose of the synchro system? ---------CORRECT ANSWER--- --------------Transfer angular info in form of voltage What is a major benefit of positive displacement pumps? ---------CORRECT ANSWER-----------------Self priming What uses the system pressure to perform the work either through linear motion or rotary motion ---------CORRECT ANSWER-----------------Actuator
What is best used to locate a suction leak on a hydraulic system? --------- CORRECT ANSWER-----------------Eye dropper filled with hydraulic fluid How does a continuous motor operate? ---------CORRECT ANSWER--------- --------Rotates without interruption when input is applied An electrical current that changes both in magnitude and direction. --------- CORRECT ANSWER-----------------alternating current AC is developed by sources called _____________. ---------CORRECT ANSWER-----------------alternators and generators A device which converts mechanical energy into an alternating electrical current. ---------CORRECT ANSWER-----------------alternator A rotating device for converting mechanical energy into an alternating electrical energy. ---------CORRECT ANSWER-----------------generator Three basic sine wave characteristics: ---------CORRECT ANSWER---------- -------frequency, period, and wavelength One cycle of AC always consists of ______________. ---------CORRECT ANSWER-----------------two alterations
The action of a conductor moving through a magnetic field causing current flow. ---------CORRECT ANSWER-----------------electromagnetic induction The effective value of an AC voltage that causes the same amount of power dissipation as a specific DC voltage. ---------CORRECT ANSWER---- -------------RMS ______ isthe relative position of AC quantities in time reference to each other. ---------CORRECT ANSWER-----------------phase RC transients occur when the _______ across a capacitor changes. --------- CORRECT ANSWER-----------------voltage What is the phase relationship between voltage and current through an inductor? ---------CORRECT ANSWER-----------------voltage leads current by 90 The currents developed by an inductor and a capacitor are 180 degrees apart in phase, their reactance: ---------CORRECT ANSWER----------------- opposes each other What is the phase relationship between current through a capacitor and an inductor? ---------CORRECT ANSWER-----------------currents are 180 apart
When the capacitor is fully charged; Ec (voltage) is the maximum and Ic (current) is ________ ---------CORRECT ANSWER-----------------minimum The relationship between frequency and the RC time constant is the principle of _______________. ---------CORRECT ANSWER----------------- capacitive reactance In a PARALLEL circuit LCR, an _____________component is recognized by no current flow in that branch ---------CORRECT ANSWER----------------- open The effect of a _______________ component in a series circuit LCR causes all voltage drops to be incorrect. ---------CORRECT ANSWER-------- ---------changed value When the inductive and capacitive reactances are equal, an LCR circuit is __________. ---------CORRECT ANSWER-----------------resonant A __________ circuit is one in which the capacitive reactance equals the inductive reactance. (Xc=Xl) ---------CORRECT ANSWER----------------- resonant A ________ component in a parallel resonant circuit is indicated by the branch current measures maximum. ---------CORRECT ANSWER------------- ----shorted
The cathode of a diode is represented by _________. ---------CORRECT ANSWER-----------------a bar N type material has _______________. ---------CORRECT ANSWER--------- --------free electrons P type material has _________. ---------CORRECT ANSWER----------------- holes The anode of a diode is represented by ___________. ---------CORRECT ANSWER-----------------an arrow How is a battery connected to foward bias a diode? ---------CORRECT ANSWER-----------------the negative side to the cathode, the positive side to the anode The primary characteristic of the diode can be described as _________________________. ---------CORRECT ANSWER----------------- changing AC current flow to DC current flow When foward biased the diode acts as a ___________. ---------CORRECT ANSWER-----------------closed switch
Resistance readings for a _________ diode indicate low resistance. --------- CORRECT ANSWER-----------------shorted A diode measuring low resistance in one direction and high in the other indicates _________________. ---------CORRECT ANSWER----------------- proper diode operation What do motion detector circuits not sense? ---------CORRECT ANSWER--- --------------Position An AC induction motor operates on the principle of what? --------- CORRECT ANSWER-----------------Induction What is localization used for? ---------CORRECT ANSWER----------------- Determine what section is faulted What type of power is produced by a generator? ---------CORRECT ANSWER-----------------AC & DC What type of acceleration is fixed between two points? ---------CORRECT ANSWER-----------------Linear What happens to the velocity of fluid in a flowing pipe if pressure decreases? ---------CORRECT ANSWER-----------------Velocity decreases
What is a symptom of relief valve stuck in the closed position? --------- CORRECT ANSWER-----------------Overheated pump Which rotary positive displacement pump has the shortest life expectancy? ---------CORRECT ANSWER-----------------Internal gear What is the term used to describe the action of starting and stopping stepper motors slower than the running speed? ---------CORRECT ANSWER-----------------EFSS What does an AC motor need as an electrical input signal? --------- CORRECT ANSWER-----------------AC;Sine wave Which type of AC motor is normally used in either large horsepower or special application devices? ---------CORRECT ANSWER----------------- Synchronous What is checking and changing the fluid level in the reservoir recommended? ---------CORRECT ANSWER-----------------To check viscosity What are two classifications of synchros? ---------CORRECT ANSWER------ -----------Control and Torque
When adjusting the rod on a flow control valve you are in essence changing what in regards to the pipe? ---------CORRECT ANSWER----------- ------Diameter Which pump provides the longest life in a typical hydraulic system? --------- CORRECT ANSWER-----------------Lube pump
