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
Description : The ring circuit of the system shown in the illustration would become inoperative if a ground developed at ____________. EL-0093 A. either terminal 'T' or 'C' B. either terminal 'B' or 'R' C. both terminals 'B' and 'C' D. both terminals 'T' and 'R'
Description : The 'T-R' circuit of the system shown in the illustration would become inoperative if a ground developed at ____________. EL-0093 A. either 'T' or 'C' B. either 'B' or 'R' C. both 'B' and 'C' D. both 'T' and 'R'
Last Answer : Answer: D
Description : The total resistance of a parallel circuit is always ____________. A. larger than that of the branch with the greatest resistance B. smaller than that of the branch with the lowest resistance C ... resistances D. equal to the sum of the individual branch resistances divided by the number of branches
Last Answer : Answer: B
Description : In the schematic of the electrical circuit shown in the illustration, what is the value of the total capacitance, when compared to the value of equal individual capacitors? EL-0038 A. Equal B. Half C. Double D. Squared
Description : In the illustrated circuit, one advantage of the capacitor coupling over direct coupling is ____________. EL-0048 A. as the frequency decreased the capacitive reactance (Xc) increases B. the amplifier becomes ... of the signal while it isolates the biasing of each stage. D. good frequency response.
Description : Power necessary to operate the horn relay shown in the illustration ____________. EL-0093 A. comes from each station's magneto B. is supplied from a 115 volt source C. is conducted through the relay's contacts D. also lights lamps 'R' and 'T'
Last Answer : Answer: A
Description : In a 15 HP induction-type motor with a cage rotor, the current required at standstill to produce starting torque is approximately ____________. A. half the full load current B. equal to the full load current C. five times the full load current D. ten to twenty times the full load current
Description : Regarding the illustrated electrical schematic, 'S1-P', 'S1-Q', and 'S1-R' represent ____________. EL-0016 A. capacitors B. normally-closed contacts C. normally-open contacts D. normally-closed pushbutton switches
Description : An open shunt field in a direct current machine may be located by connecting the field circuit to an external power source, equal to the rated field voltage or less, and tested with a voltmeter from ... C. any suitable ground to any available line lead D. any field pole to each field coil lead
Description : Etched or burned bands on the contact faces of the brushes in a direct current generator can be caused by ____________. A. high mica segments B. copper drag on the commutator C. brushes improperly positioned D. copper embedded in the brushes
Description : One method of testing for a reversed shunt field coil in a DC generator or motor is by connecting the field to a direct current source, at reduced field rated voltage, and test for ... placed near each field C. test lamp across adjacent fields D. copper jumper across the interpole connections
Description : A direct current passing through a wire coiled around a soft iron core is the description of a simple ____________. A. magnetic shield B. electromagnet C. piezoelectric device D. electromagnetic domain
Description : A step voltage E is applied to a series R-L circuit. The rate of change of current is maximum at t = _: (1) Zero (2) Infinity (3) L/R (4) R/L
Last Answer : A step voltage E is applied to a series R-L circuit. The rate of change of current is maximum at t = Zero.
Description : 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 heat sink C. aid in the removal of the heat sink D. provide maximum heat transfer
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
Description : The total resistance of a parallel circuit is always ____________. A. larger than the greatest branch resistance B. smaller than the lowest branch resistance C. equal to the sum of the individual branch resistances D. one-half the sum of the individual branch resistances
Description : For a parallel-plate capacitor with plate area "A" and plate separation "d", the capacitance is proportional to which of the following? w) A divided by d squared x) A times d y) A divided by d z) d divided by A
Last Answer : ANSWER: Y -- A DIVIDED BY D
Description : Ten coulombs of charge are placed on a solid copper sphere. Once the charge has come to rest, the ELECTRIC POTENTIAL inside the sphere is found to be: w) zero x) uniform inside the sphere and ... the sphere y) smaller than the electric potential outside the sphere z) varying as one over r squared
Last Answer : ANSWER: X -- UNIFORM INSIDE THE SPHERE AND EQUAL TO THE ELECTRIC POTENTIAL ON THE SURFACE OF THE SPHERE
Description : Five coulombs of charge are placed on a thin-walled conducting shell. Once the charge has come to rest, the electric potential inside the hollow conducting shell is found to be: w) zero x) uniform ... sphere y) smaller than the electric potential outside the sphere z) varying as one over r squared.
Last Answer : ANSWER: X -- UNIFORM INSIDE THE SPHERE AND EQUAL TO THE ELECTRIC OTENT
Description : When an operating motor is connected to the controller shown in the illustration, the a path of current flow through the circuit is ____________. EL-0010 A. 'L1', stop button, start button, coil 'CR', 'L2' B. 'L1' ... L2' D. 'L1', stop button, start button, 'CR' contact, 'M' contact, 'CR' coil, 'L2'
Description : When insulation failure produces a low resistance current path between two conductors, the resulting condition is known as ____________. A. an open B. a short circuit C. a ground D. a surge
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
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
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
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
Description : The purpose of the bias winding in figure 'B' shown in the illustration is for ____________. EL-0091 A. changing the direction of current in the control winding B. setting the operating point of the ... use of either AC or DC in the load circuit D. changing the direction of current through the load
Description : In a DC series circuit, all the conductors have the same ____________. A. power expended in them B. voltage drop across them C. resistance to current flow D. current passing through them
Description : During start-up of the circuit shown in the illustration, it is noted that the ends of component 'C' alternately glow and become dark without the tube illuminating. The most probable cause ... start the lamp D. component 'B' contacts are opening and closing thus prohibiting sufficient current flow
Description : When reading electrical motor controller diagrams, it helps to know that ____________. A. current paths in the control circuit are drawn as heavy lines and in the power circuit as lighter lines B. current ... subject to 500 volts or greater are drawn as light lines and below 500 volts as heavy lines
Description : An accidental path of low resistance, allowing passage of abnormal amount of current is known as a/an ____________. A. open circuit B. short circuit C. polarized ground D. ground reference point
Description : Moisture accumulating in electric motors and generator windings having a cold insulation resistance greater than 50,000 ohms may be baked out with internal heat. This heat can be developed by ____________. ... an electric welder and feeding it into the armature while running the motor at full speed
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
Description : In the illustrated three phase alternator, line voltage is _________. EL-0074 A. 1.73 times the phase voltage B. equal to the phase voltage C. phase voltage divided by 1.73 D. unable to answer this question without knowing the line current
Description : Proper storage battery maintenance includes ____________. A. keeping connections tight and casing surfaces clean B. making sure electrolyte level is below the separator plates C. insulating the terminals with naval jelly D. maintaining a high charging rate at all times
Description : Which of the following components are used to convert alternating current produced in the generator windings to direct current? A. Armature and equalizer B. Commutator and brushes C. Rotor and interpoles D. Field and exciter
Description : As shown in the illustration, if 'R1' and 'R2' have unequal values, the ____________. EL-0019 A. voltage drop across 'R1' will not be equal to the voltage drop across 'R2' B. current flow ... energy dissipated in 'R2' D. current flow through 'R1' will differ from the current flow through 'R2'
Description : One important difference between wye-connected and delta-connected generators is that delta connections have ____________. A. line voltages equal to the vector sum of the phase voltages B. phase voltages 90° ... C. line current equal to the phase current D. line voltage equal to the phase voltage
Description : Voltage generated by most AC generators is fed from the machine to the bus by means of ____________. A. brushes on a commutator B. brushes on slip rings C. slip rings on a commutator D. direct connections from the stator
Description : The charge flowing through a resistance `R` varies with time `t as Q = at - bt^(2)`. The total heat produced in `R` is
Last Answer : The charge flowing through a resistance `R` varies with time `t as Q = at - bt^(2)`. The total heat produced in `R` ... (3)R)/(b)` D. `(a^(3)R)/(6b)`
Description : A d.c. shunt motor runs at no load speed of 1140 r.p.m. At full load, armature reaction weakens the main flux by 5% whereas the armature circuit voltage drops by 10%. The motor full load speed in r.p.m. is (A) 1080 (B) 1203 (C) 1000 (D) 1200
Last Answer : (A) 1080
Description : Which of the following statements is true regarding the illustrated circuit? El-0069 A. This full wave bridge should never be used aboard ship because the ground on lead 'A' will show on ... be direct current suitable for electronic circuits requiring voltage regulation. D. All the above are true.
Description : Which of the following statements is true about the illustrated circuit? EL-0030 A. The field rheostat is used for manual voltage control. B. if the generator is flat compounded then the field rheostat ... to act like a series motor and overspeed with the controller in the full raise position.
Description : A device used in an electrical circuit to change alternating current to direct current, is known as a _____________. A. current transformer B. rectifier C. condenser D. shunt
Description : The use of four diodes, in a full-wave bridge rectifier circuit, will __________. A. provide unidirectional current to the load B. allow a very high leakage current from the load C. convert direct current to alternating current D. offer high opposition to current in two directions
Description : On the meter scale illustrated, while using the R X 1 scale, the reading at 'E' will be ____________. EL-0047 A. 2.0 ohms B. 20 ohms C. 200 ohms D. none of the above
Description : The counter EMF produced in the windings of a DC motor is 'zero' when the ____________. A. armature has just begun to turn B. armature is not turning C. motor is almost up to rated speed D. motor is at rated speed
Description : The hundredth part of the product of the principal (P), time (T), and rate (R) is simple interest (I), then I is _____express the statement using symb
Last Answer : The hundredth part of the product of the principal (P), time (T), and rate (R) is simple ... (I), then I is _____express the statement using symbols.
Description : Figure 'B' shown in the illustration represents a/an ____________. EL-0091 A. magnetic amplifier B. Scott-T transformer C. saturable-core reactor D. oil-filled toroid
Description : The multiple prefix 'tera' (T) means ____________. A. thousand (10 to the 3rd power) B. million (10 to the 6th power) C. billion (10 to the 9th power) D. trillion (10 to the 12th power)