The electric furnace in which heat is produced by a combination of induced current and skin effect is called __________ furnace. (A) Arc(B) Resistance(C) Low frequency induction(D) High frequency induction

The electric furnace in which heat is produced by a combination of
induced current and skin effect is called __________ furnace.
(A) Arc
(B) Resistance
(C) Low frequency induction
(D) High frequency induction
by

1 Answer

Answer :

(D) High frequency induction
by

Related questions

In low or standard frequency induction furnace, heat is produced by the (A) Combination of induced current and skin effect (B) Induction and resistance (C) Current flow through a heating element (D) None of these

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Last Answer : (B) Induction and resistance

The resistance furnace produces heat by the (A) Electric arc struck between electrodes and the charge (B) Flow of current through a heating element (C) Combination of induced current and skin effect (D) None of these

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__________ furnace is not an electric furnace. (A) Arc (B) Induction (C) Pot (D) Resistance

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The speed of a three-phase squirrel-cage induction-type motor operating in a fixed frequency system is varied by changing the _____________. A. number of phases to the motor B. number of stator poles C. locked rotor current D. resistance of the rotor winding

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In a three-phase, squirrel-cage type, induction motor the rotating magnetic field is established by the _____________. A. current induced in the rotor windings B. application of a three-phase voltage supply to the stator windings C. laminated steel core and aluminum conductors in the rotor D. interaction of the magnetic field caused by the induced current in the squirrel-cage bars with the magnetic field of the stator

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“In all cases of electromagnetic induction, an induced voltage will cause a current to flow in a closed ...

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Straight silicon steel (containing Si from 0.5 to 5%) because of their low hysteresis loss and high magnetic permeability are used for electrical appliances. Which of the following electrical appliances made of silicon steel contains maximum percentage of silicon (about 4%)? (A) Armature of small motors/generators (B) Generators and small motors (C) Induction motors (D) High frequency transformers

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Ingress of cold air in the furnaces through cracks, charging doors, openings etc(A) Reduces the flue gas temperature and makes the furnace atmosphereoxidising(B) Increases the load on the induced draft fan(C) Reduces the furnace draught(D) All (A), (B) and (C)

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If the flame is produced under the hearth and then sweeps up into the heating chamber, this is called a/an __________ furnace. (A) Sidefired (B) Underfired (C) Covered (D) Recirculating

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The arc voltage produced in A.C. circuit breaker is always (a) in phase with the arc current (b) lagging the arc current by 90" (c) leading the arc current by 90° (d) none of the above

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Nitriding of steel is done (in electric furnace) at __________ °C. (A) 510 (B) 1720 (C) 2210 (D) 910

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While the fuel fired furnace can be used upto a maximum temperature of about 1700°C, the electric furnace can be used upto a temperature of about __________ °C. (A) 2000 (B) 3000 (C) 4500 (D) 6000

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Fusion zone in the electric furnace used for reduction of phosphate rock to elemental phosphorous is maintained at __________ °C. (A) 250-300 (B) 500-750 (C) 950-1050 (D) 1400-1450

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Last Answer : (D) 1400-1450

A mixture of phosphate rock __________ is heated in an electric furnace to produce phosphorous. (A) Salt & coke (B) Sand & coke (C) And coke (D) And sand

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Last Answer : (B) Sand & coke

Electric furnace method for production of phosphorous uses phosphate rock and __________ (A) Phosphoric acid (B) Coke (C) Sulphuric acid (D) Silica and coke

Description : Electric furnace method for production of phosphorous uses phosphate rock and __________ (A) Phosphoric acid (B) Coke (C) Sulphuric acid (D) Silica and coke

Last Answer : (D) Silica and coke

Heat produced when a steady state current, I passes through an electrical conductor having resistance, 'R' is (A) IR (B) I 2R (C) IR 2 (D) I 2R

Description : Heat produced when a steady state current, I passes through an electrical conductor having resistance, 'R' is (A) IR (B) I 2R (C) IR 2 (D) I 2R

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Excessive heat in an operating motor controller can result from _____________. A. a closed starter contact B. loose connections C. missing arc chutes D. low motor starting torque

Description : Excessive heat in an operating motor controller can result from _____________. A. a closed starter contact B. loose connections C. missing arc chutes D. low motor starting torque

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Cold cracking in the heat affected zone of a high strength steel weld can take place because of the (A) Retained austenite (B) Martensite formation (C) Relatively high sulphur content in the base metal (D) Sufficient hydrogen present in the welding arc

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A capacitor and a coil are connected in series. The capacitor is charged and allowed to discharge through the coil. The current that will then flow through the capacitor-coil combination will do one of the following things. Will it: w) flow in one direction, beginning at a maximum and decreasing rapidly to zero x) oscillate indefinitely y) oscillate but diminish steadily to zero z) oscillate at high frequency at first but then at slower frequency

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Last Answer : ANSWER: Y -- OSCILLATE BUT DIMINISH STEADILY TO ZERO

An AC generator operating in parallel loses its excitation without tripping the circuit breaker. This will __________. A. not affect the faulty generator due to the compensation of the other generators B. cause the slip rings to melt C. cause a low voltage differential to develop between the armature and the bus D. cause high currents to be induced in the field windings

Description : An AC generator operating in parallel loses its excitation without tripping the circuit breaker. This will __________. A. not affect the faulty generator due to the compensation of the other generators B. ... between the armature and the bus D. cause high currents to be induced in the field windings

Last Answer : Answer: D

If the furnace is provided with insufficient fuel at low temperatures, the type of pig iron produced, is called (A) Bessemer pig (B) Grey or foundry pig (C) White or forge pig (D) Mottled pig

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When the temperature and humidity of air is low, we usually use __________ draft cooling tower. (A) Natural (B) Forced (C) Induced (D) None of these

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