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Mainly in transformers
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Description : A transformer works on the principle of (1) Self induction (2) Mutual induction (3) Generator (4) Inverter

Answer : Mutual induction

Answer : Mutual induction is dependent on current changes.

Description : The bridge method commonly used for finding mutual inductance is (A) Heaviside Campbell bridge (B) Schering bridge (C) De Sauty bridge (D) Wien bridge

Answer : The bridge method commonly used for finding mutual inductance is Heaviside Campbell bridge

Description : State the effects of errors in dynamometer type wattmeter due to i) pc- inductance ii) pc- capacitance iii) mutual inductance iv) Connection.

Answer : Errors in wattmeter:  i) pc - inductance: Pressure coil inductance causes wattmeter to read more power than actual .  ii) pc-capacitance: The wattmeter reads less power.  iii) ... iv) Connection: In uncompensated wattmeter , the reading of wattmeter includes the powerloss in coils. 

Description : The differential coupling of two coils in series connection has self-inductance of 2 mH & 4 mH & a mutual inductance of 0.15 mH. The equivalent inductance of the combination is:  (A) 5.7 mH (B) 5.85 mH (C) 6 mH (D) 6.15 mH

Description : State the function and shape of following parts used in induction type energy meter: i) Series magnet ii) Shunt magnet iii) Al disc iv) Brake magnet

Answer : i) Series magnet: produce flux proportional to current (load current) of circuit and interact in the aluminum disc with flux produced by voltage magnet for torque production. Its shape is like letter U.  ii) ... : brakes the motion of the aluminum disc or slows it down. Its shape is like letter C. 

Description : Consider the following statements with regard to induction type wattmeter :  1. Can be used on both ac and dc systems.  2. Power consumption is relatively low.  3. It is accurate only at stated frequency and temperature.  Which ... /are correct ?  (a) 1 only (b) 2 only (c) 3 only (d) 1, 2 and 3

Answer : Consider the following statements with regard to induction type wattmeter :  1. Can be used on both ac and dc systems.  2. Power consumption is relatively low.  3. It is accurate only at stated frequency and temperature. ... correct ?  (a) 1 only (b) 2 only (c) 3 only (d) 1, 2 and 3

Description : The stator of a 3 phase, 10 pole induction motor possesses 120 slots. If a lap winding is used, calculate the coil pitch, if the coil width extends from slot 1 to slot 11.  (A) 72.12% (B) 83.30% (C) 12% (D) 42% 

Answer : Mho distance relays are widely used for the protection of uncompensated and series compensated transmission lines in order to determine the presence and location of faults.

Description : Synchronous motors are to be used in situations where   (a) The load is constant. (b) The load is required to be driven at very high speeds. (c) The load is to be driven at constant speed. (d) The starting torque requirement of the load is very high. 

Answer : The material used for the magnetic circuit where high value of flux density required is ferro cobalt.

Answer : In elections devices semi conducters are used 

Description : ---------------is the ability of influencing people to strive willingly for mutual objectives (a) Motivation ; (b) Control ; (c) Leadership ; (c) Supervision

Answer :  (c) Leadership ;

Description : Define self-inductance and mutual inductance.

Answer : Self-inductance: As per the Lenz's law, the self-inducedemf opposes any current change taking place. This property of the coil to oppose any change in current flowing through it is known as the self- ... in the other coil placed nearby, by induction. It is denoted by M and measured in Henry.  

Description : Define self and mutual induced emf.

Answer : Self-induced emf: Self-induced emf is the e.m.f induced in the coil due to the change of flux produced by linking it with its own turns. Mutual induced emf: The emf induced in a coil due to the change of flux produced by another neighbouring coil linking to it, is called Mutually Induced emf.   

Description : Symposium is a Options: A) A well organised group of a few speakers with large audience B) Arrival at the certain goal through mutual exchange of ideas C) Process of taking decisions in a group D) All of the above

Answer : D) All of the above 

Description : The advantage of Conference is Options: A) Development of democratic values B) Guidance of new-researchers C) Mutual exchange of ideas D) All of the above

Answer : D) All of the above 

Description : When students are deliberately attempting to disturb the discipline of the class by making numerous mischievous like throwing of chalks, whistling upon you, calling foul and obscene words, then what ... an indirect threat D) Doing favourable efforts to judge himself and improve the mutual relations

Answer : Doing favourable efforts to judge himself and improve the mutual relations

Description : If you live on rent in your friend's house, it will be perceived by you as Options: A) Sacrifice of mutual relations B) Development of more warmth in relations C) Exposure of personal weaknesses and end of relations D) Meeting with a good co-worker who cooperate from home to school

Answer : D) Meeting with a good co-worker who cooperate from home to school 

Description : A virtual memory based memory management algorithm partially swaps out a process. This is an example of (A) short term scheduling (B) long term scheduling (C) medium term scheduling (D) mutual exclusion

Answer : (C) medium term scheduling

Description : Based on the cardinality ratio and participation ............... associated with a relationship type, choose either the Foreign Key Design, the Cross Referencing Design or Mutual Referencing Design. (A) Entity (B) Constraints (C) Rules (D) Keys

Answer : (B) Constraints

Description : ‘Residex’ is associated with (1) Share prices (2) Price inflation (3) Mutual fund prices (4) Land prices 

Answer :  Land prices

Description : A short-term government security paper is called (1) Share (2) Debenture (3) Mutual fund (4) Treasury bill

Answer : Treasury bill

Description : A three-phase synchronous motor has a terminal voltage of 460 V and a terminal current of 120 A at a power factor of 0.95 lagging, synchronous reactance of 1.68 ohm and the field current is 47 A. The field to armature mutual ... _____________.      (a). 20mH   (b). 16mH   (c). 24mH   (d). 22mH

Answer : 22

Description : Coefficient of Mutual inducatance (M)

Description : Mutual inductance

Description : Mutual inductance between two magnetically coupled coils depends on (a) number of turns only (b) permeability of the core only (c) cross-sectional area of their common core only (d) All of the above 

Description : In a Hartley oscillator, L1 = 0.1 mH, L2 = 10 µH and mutual inductance between coils equals 20 µH. The voltage gain needed for sustained oscillations should be (a) 2.37 (b) 0.1 (c) 11.54 (d) 9.09 

Answer : For measurement of mutual inductance we can use Heaviside bridge.

Description : ............... is often used to prove the correctness of a recursive function. (A) Diagonalization (B) Communitivity (C) Mathematical Induction (D) Matrix Multiplication

Answer : (C) Mathematical Induction

Description : A device used for converting a.c. into d.c. is called (1) transformer (2) recticfier (3) induction coil (4) dynamo

Answer : recticfier

Description : Develop the control circuit for star-delta starter used for starting a 3 ∅ induction motor.

Answer : Control Circuit for Star-Delta Starter: 1) Automatic Star-Delta Starter: OR 2) Semi- automatic Star-Delta Starter:

Description : Explain DOL starter used for 3 phase induction motor.

Answer : DOL Starter Used for 3 Phase Induction Motor: The direct online starter consist of overload relay (OLC), contactor, start-push button S1 (normally open), stop-push button S2 (normally ... The overload coil (OLC) protects the motor against overload and short circuit by opening the contact D.

Description : State starters used for i) 3-Ph squirrel cage induction motor (3HP) ii) D.C. motor 

Answer : Name the starters used for following motors : i) 3 H.P. 3-Ph squirrel cage I.M: i) DOL starter OR ii) Star-Delta Starter OR ii) Auto transformer starter OR iii) Soft start starter.  ii) D.C Shunt Motor : 1) Armature resistance starter (Three Point Starter) OR 2) Four Point Starter 

Description : In a 3-phase voltage source inverter used for speed control of induction motor, anti-parallel diodes are used across each switching device. The main purpose of diodes is to:

Answer : In a 3-phase voltage source inverter used for speed control of induction motor, anti-parallel diodes are used across each switching device. The main purpose of diodes is to: Allow the motor to return energy during regeneration

Description : Deep bar rotor construction is used in three phase induction motors to mainly: (1) Control speed (2) Control power factor (3) Increase starting torque (4) None of these

Answer : Deep bar rotor construction is used in three phase induction motors to mainly: Increase starting torque

Description : Consider the following statements: Star delta starter is used in 3-phase induction motor because it  1. Prevents heating of the motor winding  2. Ensures permissible minimum starting current  3. Is regulated by electricity ... and 4 are correct (c) 1, 3 and 4 are correct (d) 1 and 2 are correct 

Answer : Consider the following statements: Star delta starter is used in 3-phase induction motor because it  1. Prevents heating of the motor winding  2. Ensures permissible minimum starting current  3. Is regulated by ... and 4 are correct (c) 1, 3 and 4 are correct (d) 1 and 2 are correct 

Description : The range of frequencies used in induction heating is :  (A) 0-25 Hz  (C) less than 200 Hz  (B) 50 to 100 Hz  (D) more than 1 kHz

Answer : The range of frequencies used in induction heating is : more than 1 kHz

Answer : An induction wattmeter can be used for A.C. 

Answer : For handling greater currents induction wattmeters are used in conjunction with current transformers.

Answer : The repulsion-start induction-run motor is used because of high starting torque.

Answer : if induction motor rotates exceed than its synchronous speed, it acts as a generator.

Description : State the situations where oil paint and distempers are used.

Answer : situations where oil paint are used: 1. It can be used on dry surface (damp free), on wood & metal works. For enhancing the appearance. 2. To protect the metals works from corrosion. 3. To ... Used on wall boards. 3. To enhance the appearance of plaster. 4. To increase life of plaster. 

Description : Suggest the type of cement used for the following : (i) For modular construction where form work needs to be removed early for re-use. . (ii) Mass concreting such as construction of dam. (iii) Decorative works in external surfaces of building. (iv) Cementing the oil well.

Answer : i) For modular construction where form work needs to be removed early for reuse. – Rapid Hardening Cement ii) Mass concreting such as construction of dam. – Low heat cement. iii) Decorative works in external surfaces of building – Coloured cement. iv) Cementing the oil well. – Oil Well Cement. 

Description : Write the situations where Geo-synthetic material products and artificial timber is used.

Answer : Geosynthetic material products are used in following situations1) When there is a possibility of piping i.e. soil movement due to movement of water. To prevent soil movement (piping), while letting ... ) When it is necessary to improve the appearance with the use of artificial timber for flooring.

Description : State the situations where following paints are used: (i) Oil paints (ii) Distempers (iii) Varnishes (iv) Cement paints

Answer : Situations where following paints are used: 1) Oil paints: structural steel members to protect from corrosion, wooden doors and windows, walls, ceilings, to protect from insects. 2) Distempers : ... wood surfaces. 4) Cement paint: on external walls of building, stone masonry, concrete surfaces

Description : State situations where sound insulating and damp proofing materials are used. 

Answer : Situations where sound insulating materials are used: 1) Glass, mineral wool mats, are used as sound insulators as solid inner layers underneath floors, 2) Wood fibre and asbestos cement slabs are used ... in toilet floors of upper story, so that no dampness will occur in slab below that floor.

Description : State any four situations where hollow concrete block masonry is used.

Answer : Situations where hollow concrete block masonry is used. 1) Hollow concrete blocks are fire resistant and hence are used in masonry where fire resistance is necessary, like furnace, chimney etc. ... . 6) They are used to achieve lower labor involvement and greater durability, like Retaining walls

Description : Where is snail mucus used?

Answer : Snail mucus products have revolutionized the field of cosmetology. Leading global brands are actively developing their own lines of cosmetics, with a high content of snail extract. And the higher the ... based on snail mucus. Using several products from the same series will also enhance the effect.

Description : What is roofing mastic and where is it used?

Answer : Modern building materials make it possible to equip soft flat roofs without resorting to the usual roll materials, and this significantly reduces the time of work and provides a uniform, ... with water; diluted with organic solvents; diluted with solvents, containing liquid organic substances.

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