Description : Materials that retain a large part of their magnetization, after the magnetizing force is removed, are said to have _____________. A. low hysteresis loss B. high flux density C. high permanence D. high permeability
Last Answer : Answer: C
Description : As an armature revolves within a magnetic field, friction is developed between the rotated magnetized particles as they pass through each magnetization cycle. This results in ____________. A. copper loss B. eddy-current loss C. hysteresis loss D. armature reaction
Description : Iron filings can be separated from a heterogenous mixture using the technique of (1) Sublimation (2) Magnetization (3) Sedimentation (4) Evaporation
Last Answer : (2) Magnetization Explanation: The method of separation using magnets is used when one of the components is magnetic. So the heterogeneous mixture of iron filings and some other material (such as sulphur ... by using magnets. Similarly, a mixture of sand and iron filings can be separated by magnet.
Description : The method of magnetization is: (1) hammering a magnet (2) heating a magnet (3) passing direct current through it (4) passing alternating current through it
Last Answer : (1) hammering a magnet Explanation: Hammering a rod will either allow it to become slightly magnetic inlaid along a magnetic field (i.e.North - South) or demagnetize it if laid across the field lines (i.e. East-West). A current passing through a coil will produce a magnetic field.
Description : In the process of magnetization of a bar (1) The entire bulk of the bar gets magnetized (2) Only the surface of the bar gets magnetized (3) Only the ends of the bar get magnetized (4) Only some parts of the outer layers of the bar get magnetized
Last Answer : (1) The entire bulk of the bar gets magnetized Explanation: In classical electromagnetism, magnetization or magnetic polarization is the vector field that expresses the density of permanent or induced magnetic ... the process of magnetization of a bar, the entire bulk of the bar gets magnetized.
Description : The charge build up in a capacitor is due to a) Conduction current density b) Displacement current density c) Polarisation d) Magnetization
Last Answer : b) Displacement current density
Description : The reason for non existence of magnetic monopoles is a) The magnetic field cannot be split b) Due to permeability c) Due to magnetization d) Due to magnetostriction
Last Answer : a) The magnetic field cannot be split
Description : The energy in a magnetic material is due to which process? a) Emf b) Magnetization c) Magnetostriction d) Polarization
Last Answer : b) Magnetization
Description : A boundary of separation between two magnetic materials is identified by which factor? a) Change in the permeability b) Change in permittivity c) Change in magnetization d) Conduction
Last Answer : a) Change in the permeability
Description : Find the magnetic moment of a material with magnetization 5 units in a volume of 35 units. a) 7 b) 1/7 c) 15 d) 175
Last Answer : d) 175
Description : Find the magnetization of the material with susceptibility of 6 units and magnetic field intensity of 13 units. a) 2.16 b) 6.2 c) 78 d) 1.3
Last Answer : c) 78
Description : Find the correct relation between current density and magnetization. a) J = Grad(M) b) J = Div(M) c) J = Curl(M) d) M = Curl(J)
Last Answer : c) J = Curl(M)
Description : Calculate the magnetization of a material with susceptibility of 50 and field intensity of 0.25 units. a) 12.5 b) 25 c) 75 d) 37.5
Last Answer : a) 12.5
Description : The expression for magnetization is given by(I-current, A-area, V-volume) a) M = IAV b) M = IA/V c) M = V/IA d) M = 1/IAV
Last Answer : b) M = IA/V
Description : The converse of magnetostriction is called the a) Magnetization b) Magnetic anisotropy c) Villari effect d) Curie effect
Last Answer : c) Villari effect
Description : Piezoelectric effect is analogous to which phenomenon? a) Electrostriction b) Magnetostriction c) Anisotropy d) Magnetization
Last Answer : b) Magnetostriction
Description : Find the internal field when the applied field is 12 units, molecular field constant is 0.1 units and the magnetization is 74 units. a) 86 b) 62 c) 752 d) 19.4
Last Answer : d) 19.4
Description : Find the magnetization of the field which has a magnetic moment 16 units in a volume of 1.2 units. a) 16.67 b) 13.33 c) 15.56 d) 18.87
Last Answer : b) 13.33
Description : The magnetization is defined by the ratio of a) Magnetic moment to area b) Magnetic moment to volume c) Magnetic flux density to area d) Magnetic flux density to volume
Last Answer : b) Magnetic moment to volume
Description : The inductance is the measure of a) Electric charges stored by the material b) Emf generated by energising the coil c) Magnetic field stored by the material d) Magnetization of dipoles
Last Answer : c) Magnetic field stored by the material
Description : When a dielectric loses its dielectric property, the phenomenon is called a) Dielectric loss b) Dielectric breakdown c) Polarisation d) Magnetization
Last Answer : b) Dielectric breakdown
Description : The superconducting materials will be independent of which of the following? a) Magnetic field b) Electric field c) Magnetization d) Temperature
Last Answer : b) Electric field
Description : At what portion of the magnetization curve should a magnetic amplifier be operated?
Last Answer : . The knee of the curve.
Description : The loss of energy over each A.C cycle magnetization and demagnetization of transformer, is called: a. Magnetization loss b. Hysteresis loss c. Demagnetization loss d. energy loss
Last Answer : c. Demagnetization loss
Description : Entropy is a measure of: w) magnetization x) disorder y) temperature z) heat
Last Answer : ANSWER: X -- DISORDER
Description : Iron filings can be separated from a heterogenous mixture using the technique of : (1) Sublimation (2) Magnetization (3) Sedimentation (4) Evaporation
Last Answer : Magnetization
Description : The total magnetic moment 1. is called saturation magnetization. 2. depends on the number of magnetic dipoles per unit volume, the instant electric current and the area of the current loop. Which of the above statements is/are correct ?
Last Answer : depends on the number of magnetic dipoles per unit volume, the instant electric current and the area of the current loop
Description : Which of the methods listed is used to maintain the division of load between two compound-wound, DC generators operating in parallel? A. The shunt fields are interconnected. B. The shunt ... generators are connected in series. D. The equalizer connection parallels the series fields of all machines.
Last Answer : Answer: D
Description : Which of the methods listed is used to start a AC generator turning? A. Residual magnetism remaining in the field poles. B. Residual magnetism remaining in the field coils. C. Residual magnetism remaining in the armature. D. Rotation by a mechanical prime mover.
Description : Under normal conditions, storage batteries used for starting the emergency diesel generator are maintained in a charged state by which of the following methods? A. Trickle charging B. Fast charging C. Equalizing charge D. Reverse charging
Last Answer : Answer: A
Description : The operator of electrical motors should keep a constant check on the loads they carry because _____________. A. low loads necessitate frequent insulation cleaning B. exceeding nameplate values shortens ... wasted if full loading is not utilized D. power factor correction methods are load dependent
Last Answer : Answer: B
Description : Which of the following methods should be used to test for an 'open' coil in an AC motor stator? A. Test with an ohmmeter, one test lead on the shaft, and the other test lead to the stator leads ... an open coil. D. Use a growler, listening for noise and vibration to increase when over an open coil.
Description : Which of the following methods should be used to dress the face of silver-plated contacts? A. Filing B. Burnishing C. Sanding with 0000 sandpaper D. All of the above are correct.
Description : Which of the methods listed is used to maintain equal load sharing between two compound wound DC generators operating in parallel? A. The shunt fields are interconnected. B. The shunt field rheostats ... are connected in series. D. The series fields of both generators are connected in parallel.
Description : Methods to control speed of Wound Rotor Motors?
Last Answer : The speed of wound rotor motors are changed by changing the slip of the motor. This can be achieved by: Varying the stator line voltage Varying the resistance in the rotor circuit Inserting and varying a foreign voltage source in the rotor circuit
Description : What are methods available for making single phase induction motor a self starting?
Last Answer : By slitting the single phase, by providing shading coil in the poles.
Description : What are the two methods of control in ac voltage controllers?
Last Answer : a. ON-OFF control b. Phase control
Description : What are the methods of reduction of harmonic content?
Last Answer : a. Transformer connections b. Sinusoidal PWM c. Multiple commutation in each cycle d. Stepped wave inverters
Description : What are the different methods of firing circuits for line commutated converter?
Last Answer : a. UJT firing circuit. b. The cosine wave crossing pulse timing control. c. Digital firing schemes.
Description : What are the different methods to turn on the thyristor?
Last Answer : a. Forward voltage triggering b. Gate triggering c. dv/dt triggering d. Temperature triggering e. Light triggering
Description : What are the different turn on methods of SCR?
Last Answer : Forward voltage triggering Gate Triggering dv/dt triggering Temperature triggering Light triggering
Description : What are the methods of checking the phase difference?
Last Answer : 1. All Dark lamp method 2. Two bright one dark lamp method 3. Synchroscope
Description : Name the various methods for predetermining the voltage regulation of 3-phase Alternator.
Last Answer : The following are the three methods which are used to predetermine the voltage regulation of smooth cylindrical type Alternators · Synchronous impedance / EMF method · Ampere-turn / MMF method · Potier / ZPF method
Description : List some methods of cooling of transformers.
Last Answer : A:Air natural, Air blast, Oil Natural, Oil natural air forced, Oil natural water forced, Oil forced, Oil forced air natural, Oil forced air natural, Oil forced water forced.
Description : What are the methods adopted to reduce harmonic torques?
Last Answer : The methods used for reduction or elimination of harmonic torques are chording, integral slot winding, skewing and increasing the length of air gap.
Description : List out the methods to improve the power factor of the induction motor.
Last Answer : The power factor of the induction motor can be improved by reducing the magnetizing current and leakage reactance. The magnetizing current can be reduced by reducing the length of air gap. The ... stator & rotor slots, by providing short chorded winding and reducing the overhang in stator winding.
Description : List out the methods of speed control of cage type 3-phase induction motor?
Last Answer : a) By changing supply frequency b) By changing the number of poles c) By operating two motors in cascade
Description : What are the methods for determining depreciation charges?
Last Answer : The decrease in the value of the power plant equipment and building due to constant use is known as depreciation. The cost of depreciation will depend on the size and type of equipment ... equals the cost of equipment. The methods commonly used for determination of annual depreciation charges are
Description : What are the advantages of synthetic testing methods?
Last Answer : The breaker can be tested for desired transient recovery voltage and RRRV. Both test current and test voltage can be independently varied. This gives flexibility to the test The method is simple With ... capacity (MVA) of five time of that of the capacity of the test plant can be tested.
Description : What are the indirect methods of circuit breaker testing?
Last Answer : o Unit test o Synthetic test o Substitution testing o Compensation testing o Capacitance testing