Description : A saturable-core reactor operates on the principle of controlling a load winding's inductance by varying the core's _____________. A. dielectric B. permeability C. reactance D. inductance
Last Answer : Answer: B
Description : The point of operation for a saturable reactor in a power circuit is that at which _______________. A. a large change in control current results in small change in load current B. a small change in ... change in load current D. a large change in load current causes a small change in control current
Last Answer : Answer: C
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
Last Answer : Answer: A
Description : Figure 'A' 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 : An electrical device which employs a stationary armature and a rotating electromagnetic field is used aboard ship as a ____________. A. magnetic amplifier B. ship's service alternator C. three-wire DC generator D. saturable core reactor
Description : Although saturable reactors are extremely useful in some applications, their gain is low because of ____________. A. core hysteresis losses B. inductive reactance in the control winding C. IR drop throughout the load winding D. all of the above
Description : Basically, a magnetic amplifier is a saturable reactor with the addition of _____________. A. AC to the bias winding B. variable capacitance to all windings C. eddy current protectors D. a rectifier in the load circuit
Last Answer : Answer: D
Description : A saturable reactor uses relatively small DC currents to control _______________. A. high frequency low power loads B. low frequency low power loads C. high frequency high power loads D. low frequency high power loads
Description : Justify the use of saturable reactor to control the magnitude of welding current.
Last Answer : .embed-container { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; } .embed-container iframe, .embed-container object, .embed-container embed { position: absolute; top: 0; left: 0; width: 100%; height: 100%; }
Description : The voltage at the reference electrode of the circuit shown in the illustration is applied to the input of a/an ______________. EL-0090 A. class A detector whose output drives an ... drives an 2-stage isolation transformer D. magnetic amplifier whose output controls a saturable reactor
Description : Figure 'A' of the diagram shown in the illustration represents a ______________. EL-0092 A. differential transformer B. saturable reactor C. synchro system D. magnetic amplifier
Description : The horizontal line which cuts across 'L1' shown in figure 'A' of the illustration indicates a/an ______________. EL-0091 A. iron core B. saturable core C. air gap D. capacitive coupling
Description : The secondary output voltage of a saturable core frequency meter is the function of (a) only frequency (b) only primary voltage (c) both (a) and (b) (d) None of above
Last Answer : C) Both a and b
Description : The core flux of a practical transformer with a resistive load A) Is strictly constant with load changes B) Increases linearly with load C) Increases as the square root of the load D) Decrease with increased load
Last Answer : The core flux of a practical transformer with a resistive load Is strictly constant with load changes
Description : What effect does flux leakage in a transformer have on the coefficient of coupling (K) in the transformer?
Last Answer : it causes K to be less than unity (I).
Description : What type of current is eliminated by synchro capacitors?
Last Answer : Magnetizing current.
Description : Which of the following reactors is operated at high neutron flux and low power level? (A) Breeder reactor (B) Research reactor (C) Heterogeneous reactor (D) Liquid metal (e.g., molten sodium) cooled reactor
Last Answer : (B) Research reactor
Description : Primary purpose of a __________ nuclear reactor is to supply a high neutron flux of the order of 10 13 to 10 14neutrons/cm2 second. (A) Research (B) Power (C) Breeder (D) Homogeneous
Last Answer : (A) Research
Description : Glucose uptake by liver cells is (A) Energy-consuming (B) A saturable process (C) Insulin-dependent (D) Insulin-independent
Last Answer : D
Description : Active transport of a substance across biological membranes has the following characteristics except: A. It is specific B. It is pH dependent C. It is saturable D. It requires metabolic energy
Last Answer : B. It is pH dependent
Description : Which word(s) could be eliminated for a stronger effect Please give my regards to each and every one of my former students?
Last Answer : each and.(each and) You're welcome, J 2021. 2/23/2021 11:46 PM
Description : Why not reduce the noise in the core by reducing the amount of flux?
Last Answer : Transformer voltages are fixed by system requirements. The ratio of these voltages to the number of turns in the winding determines the amount of magnetization. This ratio of voltage to turns is determined ... flux at the normal voltage is fixed. This also fixes the level of noise and vibration.
Description : In transformer, the core is made up of soft iron in order to pass the maximum A. flux B. current C. magnetic flux D. voltage
Last Answer : magnetic flux
Description : The relay operating speed depends upon (a) the spring tension (b) the rate of flux built up (c) armature core air gap (d) all of the above
Last Answer : (d) all of the above
Description : [53] The iron loss of the transformer is negligible during short circuit test because A. The entire input is just sufficient to meet Cu losses only B. Flux produced is a small fraction of the normal flux C. Iron core becomes fully saturated D. Supply frequency is held constant
Last Answer : B. Flux produced is a small fraction of the normal flux
Description : [31] With both S1 and S2 open, the core flux waveform will be [GATE 2009] A. a sinusoidal at fundamental frequency B. flat-topped with third harmonic C. peaky with third-harmonic D. none of these
Last Answer : B. Flat topped with third harmonic
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 : 12] Which is not the basic element of the transformer? A. core B. primary winding C. secondary winding D. mutual flux
Last Answer : D. Mutual flux
Description : Which of the following iron core electromagnets creates the greatest amount of magnetic flux: w) 1,000 coils, 2 amps of current x) 250 coils, 7 amps of current y) 700 coils, 3 amps of current
Last Answer : ANSWER: Y -- 700 COILS, 3 AMPS OF CURRENT
Description : The core of a transformer (medium size) uses to provide high flux densities (a) diamagnetic (c) ferromagnetic core (b) paramagnetic (d) none of these
Last Answer : The core of transformer is made up colled rolled grain oriented. It is a ferromagnetic material..
Description : A boiling water reactor is the one, in which the (A) Coolant water is allowed to boil in the core of the reactor (B) Coolant water, after being heated in the reactor core, generates steam ... water is pumped into the core (D) Fuel and the coolant are thoroughly mixed to form a homogeneous solution
Last Answer : (A) Coolant water is allowed to boil in the core of the reactor
Description : In a pressurised water reactor (PWR), the (A) Fuel is natural uranium and heavy water acts both as moderator & coolant (B) Coolant water boils in the core of the reactor (C) Coolant water is pressurised to prevent bulk boiling of water in the core (D) Use of moderator is not required
Last Answer : (C) Coolant water is pressurised to prevent bulk boiling of water in the core
Description : Molten sodium is used as a coolant in a fast breeder reactor, because of its (A) Excellent moderating properties (B) Neutron breeding capability (C) Faster heat removal capability from the core (D) Capability to increase the reaction rate in the core
Last Answer : (C) Faster heat removal capability from the core
Description : Secondary cooling circuit is a must in molten sodium cooled fast breeder reactor for (A) Achieving high degree of superheat in the steam (B) Faster heat removal rate from the core (C) ... circulation pressure (D) Avoiding the mixing of water with radioactive sodium, as it may cause explosion
Last Answer : (D) Avoiding the mixing of water with radioactive sodium, as it may cause explosion
Description : Use of molten metal as a coolant in fast breeder reactor helps in (A) Rapid heat transfer from the core (B) Accelerating the reaction rate in the core (C) Breeding neutrons (D) Accelerating the neutrons
Last Answer : (A) Rapid heat transfer from the core
Description : What type of flux must be used in all electrical and electronic soldering?
Last Answer : Noncorrosive, nonconductive rosin fluxes.
Description : What purpose does flux serve in the soldering process?
Last Answer : It cleans the metal by removing the oxide layer and prevents further oxidation during the soldering
Description : What is "leakage flux?"
Last Answer : Lines of flux generated by one winding which do not link the other winding.
Description : What type(s) of flux should never be used on electronic equipment?
Last Answer : Chloride or (acid) and organic.
Description : Flux aids in soldering by removing what from surfaces to be soldered?
Last Answer : Oxides.
Description : The risk that the audit will fail to uncover a material misstatement is eliminated a. When the auditor has complied with generally accepted auditing standards. b. If client has good internal control. c. If client follows generally accepted accounting principles. d. Under no circumstances
Last Answer : Under no circumstances
Description : The basic control action of a magnetic amplifier depends upon _____________. A. variations in the load capacitance B. changes in inductance C. type of core material D. construction of the core
Description : What is the advantage of using a closed-servo loop to control load velocity?
Last Answer : The closed-servo loop can regulate load speed under changing conditions.
Description : In an open-loop control system, what action reduces the input to zero so the load is stopped at the desired position?
Last Answer : Usually the operator senses the desired load movement and reduces the input to stop the motor.
Description : A tube has a transconductance of 800 mhos and a load resistor of 50 kohms. When control grid voltage varies by 6 volts, the plate voltage will vary by what amount?
Last Answer : 240 volts.
Description : If two coils are wound on a single iron core, what will a change in current in one coil cause in the other coil?
Last Answer : A change in inductance.
Description : What happens to the permeability of an iron core as the current increases from the operating point to a large value?
Last Answer : Permeability decreases