The temperature of resistance furnaces can be controlled by changing the:

The temperature of resistance furnaces can be controlled by changing the: (A) applied voltage (B) number of heating elements (C) circuit configuration (D) all of the above
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The temperature of resistance furnaces can be controlled by changing the: (A) applied voltage (B) number of heating elements (C) circuit configuration (D) all of the above

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The temperature of resistance furnaces can be controlled by changing the: (A) applied voltage (B) number of heating elements (C) circuit configuration (D) All of the above

Description : The temperature of resistance furnaces can be controlled by changing the: (A) applied voltage (B) number of heating elements (C) circuit configuration (D) All of the above

Last Answer : Ans: D Temperature of resistance furnaces can be controlled by changing either applied voltage or by number of heating elements or by circuit configuration.

Pasteurisation of milk means (A) Removal of fatty and albuminous substance from it (B) Killing of organisms present in it by heating it at controlled temperature without changing its natural characteristics (C) Inhibiting the growth of micro-organisms without killing them (D) None of these

Description : Pasteurisation of milk means (A) Removal of fatty and albuminous substance from it (B) Killing of organisms present in it by heating it at controlled temperature without changing its natural characteristics (C) Inhibiting the growth of micro-organisms without killing them (D) None of these

Last Answer : (B) Killing of organisms present in it by heating it at controlled temperature without changing its natural characteristics

Thermocol (expanded polystyrene) is not used for (A) Low temperature thermal insulation as in refrigerator and air conditioners (B) Acoustic control and ceiling for building (C) High temperature thermal insulation in furnaces (D) Packing of delicate electronic gadgets

Description : Thermocol (expanded polystyrene) is not used for (A) Low temperature thermal insulation as in refrigerator and air conditioners (B) Acoustic control and ceiling for building (C) High temperature thermal insulation in furnaces (D) Packing of delicate electronic gadgets

Last Answer : (C) High temperature thermal insulation in furnaces

In furnaces operating at very high temperature (say) 1250°C, e.g. soaking pit), the maximum heat transfer takes place by (A) Conduction (B) Convection (C) Radiation (D) Cannot be predicted

Description : In furnaces operating at very high temperature (say) 1250°C, e.g. soaking pit), the maximum heat transfer takes place by (A) Conduction (B) Convection (C) Radiation (D) Cannot be predicted

Last Answer : (C) Radiation

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)

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

Last Answer : (D) All (A), (B) and (C)

The heat recoverable from flue gases of furnaces depends on the (A) Thermal efficiency of furnace (B) Quantity of flue gases (C) Flue gas temperature drop through the furnace (D) All (A), (B) and (C)

Description : The heat recoverable from flue gases of furnaces depends on the (A) Thermal efficiency of furnace (B) Quantity of flue gases (C) Flue gas temperature drop through the furnace (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Maximum heat transfer in high temperature furnaces is by (A) Conduction (B) Convection (C) Radiation (D) Either (A), (B) or (C); depends on the type of furnace

Description : Maximum heat transfer in high temperature furnaces is by (A) Conduction (B) Convection (C) Radiation (D) Either (A), (B) or (C); depends on the type of furnace

Last Answer : (C) Radiation

Forced recirculation of furnace gases is practised (A) To increase heat transfer by convection (B) To ensure uniform temperature (C) In furnaces, operating below 750°C (D) All (A), (B) and (C)

Description : Forced recirculation of furnace gases is practised (A) To increase heat transfer by convection (B) To ensure uniform temperature (C) In furnaces, operating below 750°C (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Soft coke is not (A) Produced by low temperature carbonisation of coal (B) A domestic fuel (C) Used in blast furnaces (D) None of these

Description : Soft coke is not (A) Produced by low temperature carbonisation of coal (B) A domestic fuel (C) Used in blast furnaces (D) None of these

Last Answer : (C) Used in blast furnaces

Pick out the wrong statement. (A) LPG is also used as fuel for automobiles & small furnaces and for cutting & welding of metals (B) The minimum temperature, at which a petroleum oil vapor catches fire and continues to burn, is called its flash point (C) Each ton of petroleum oil on distillation produces about 30-50 Nm3 of gas (D) Maximum yield of naphthalene is obtained on distillation of crude oil

Description : Pick out the wrong statement. (A) LPG is also used as fuel for automobiles & small furnaces and for cutting & welding of metals (B) The minimum temperature, at which a petroleum oil vapor catches ... about 30-50 Nm3 of gas (D) Maximum yield of naphthalene is obtained on distillation of crude oil

Last Answer : (B) The minimum temperature, at which a petroleum oil vapor catches fire and continues to burn, is called its flash point

are portable devices capable of estimating the combusting efficiency of furnaces, boilers, or other fossil fuel burning machines. a) Sound analyzer. c) Combustion analyzer. b) Light analyzer. d)Temperature analyzer

Description : are portable devices capable of estimating the combusting efficiency of furnaces, boilers, or other fossil fuel burning machines. a) Sound analyzer. c) Combustion analyzer. b) Light analyzer. d)Temperature analyzer

Last Answer : Combustion analyzer. 

are portable devices capable of estimating the combusting efficiency of furnaces, boilers, or other fossil fuel burning machines. a) Sound analyzer. b) Light analyzer. c) Combustion analyzer. d) Temperature analyzer.

Description : are portable devices capable of estimating the combusting efficiency of furnaces, boilers, or other fossil fuel burning machines. a) Sound analyzer. b) Light analyzer. c) Combustion analyzer. d) Temperature analyzer.

Last Answer : Combustion analyzer.

Process based multitasking is totally controlled by the

Description : Process based multitasking is totally controlled by the  A) program B) thread C) operating system D) none of the above

Last Answer : Process based multitasking is totally controlled by the operating system

The voltage output of an AC generator is accurately controlled by _____________. A. changing the sensitivity of the prime mover to large changes in voltage B. varying the reluctance of the air gap C. varying the DC exciter voltage D. shorting out part of the armature windings

Description : The voltage output of an AC generator is accurately controlled by _____________. A. changing the sensitivity of the prime mover to large changes in voltage B. varying the reluctance of the air gap C. varying the DC exciter voltage D. shorting out part of the armature windings

Last Answer : Answer: C

In voltage source converter based HVDC transmission system the active power is controlled by changing

Description : In voltage source converter based HVDC transmission system the active power is controlled by changing (A) phase angle of the converter ac input voltage (B) supply frequency of the converter ac input voltage (C) magnitude of the converter ac input voltage (D) DC voltage at the inverter terminals

Last Answer : In voltage source converter based HVDC transmission system the active power is controlled by changing phase angle of the converter ac input voltage

Is it a law that the phone must ring while you're in the shower, and hot water heaters and furnaces must break down on Holiday long weekends?

Description : Is it a law that the phone must ring while you're in the shower, and hot water heaters and furnaces must break down on Holiday long weekends?

Last Answer : It’s a Laws of the Universe thing.

(i) How is it advantageous for a mini steel plant— (1) to use electric furnaces (2) not to be located close to the location of the raw material ? -Geography

Description : (i) How is it advantageous for a mini steel plant— (1) to use electric furnaces (2) not to be located close to the location of the raw material ? -Geography

Last Answer : (i) (1) Mini Steel Plants use electric furnaces as it becomes easy for these plants scatter all over the country, and coal is also conserved. (2) These steel plants are not located close to the ... Bhilai gets its Iron from Dalli-Rajhare Mines and Coal from Kargati of M.P., Bokaro and Jharia also.

Which is better boilers or gas furnaces?

Description : Which is better boilers or gas furnaces?

Last Answer : Furnaces heat air and distribute through the ducts in your home, while boilers heat water providing steam for heat. Both are similiar and can be energy effecient, depending which one you end up choosing. It really is a matter of preference, and of course the cost of installation.

LSHS is a type of furnace oil, which (A) Is more viscous than high viscosity furnace oil (HVFO) (B) Stands for low sulphur heavy stock (C) Is an ideal fuel for metallurgical furnaces due to its lower sulphur content (< 1%(D) All (A), (B) and (C))

Description : LSHS is a type of furnace oil, which (A) Is more viscous than high viscosity furnace oil (HVFO) (B) Stands for low sulphur heavy stock (C) Is an ideal fuel for metallurgical furnaces due to its lower sulphur content (< 1%) (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Why refractory metals are used in construction of furnaces ?

Description : Why refractory metals are used in construction of furnaces ?

Last Answer : Ans. Refractory metals are used in construction of furnaces because they can withstand high temperature.

Which of the following furnaces will have maximum thermal efficiency? (A) Soaking pits (B) Walking beam reheating furnace (C) Boiler furnace (D) Rotary kilns

Description : Which of the following furnaces will have maximum thermal efficiency? (A) Soaking pits (B) Walking beam reheating furnace (C) Boiler furnace (D) Rotary kilns

Last Answer : (C) Boiler furnace

Thickness of stock does not affect the fuel economy of furnaces, if thematerial to be heated is of(A) Low emissivity(B) High thermal conductivity(C) Both (A) and (B)(D) Neither (A) nor (B)

Description : Thickness of stock does not affect the fuel economy of furnaces, if thematerial to be heated is of (A) Low emissivity (B) High thermal conductivity (C) Both (A) and (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) and (B)

Thermal efficiency of furnaces can be improved by (A) Waste heat recovery from flue gas (B) Minimising heat losses from furnace walls(C) Maintaining proper draught(D) All (A), (B) and (C

Description : Thermal efficiency of furnaces can be improved by (A) Waste heat recovery from flue gas (B) Minimising heat losses from furnace walls (C) Maintaining proper draught (D) All (A), (B) and (C

Last Answer : (D) All (A), (B) and (C

Fuel economy in furnaces can be achieved by (A) Using oxygen enriched combustion air (B) Preheating the combustion air (C) Reducing the heat loss through furnace openings & doors (D) All (A), (B) and (C

Description : Fuel economy in furnaces can be achieved by (A) Using oxygen enriched combustion air (B) Preheating the combustion air (C) Reducing the heat loss through furnace openings & doors (D) All (A), (B) and (C

Last Answer : (D) All (A), (B) and (C

Shaft furnaces are used for (A) Smelting (B) Calcining (C) Roasting (D) All (A), (B) and (C)

Description : Shaft furnaces are used for (A) Smelting (B) Calcining (C) Roasting (D) All (A), (B) and (C)

Last Answer : Corporate Strategy

Hearth furnaces are not used for (A) Roasting (B) Melting (C) Reheating (D) None of these

Description : Hearth furnaces are not used for (A) Roasting (B) Melting (C) Reheating (D) None of these

Last Answer : (D) None of these

Means for giving direction to the circulation of gases in furnaces are (A) Fans (B) Arrangement of heating stock in the furnaces (C) Location of outlet ports and heating & combustion devices (D) All (A), (B) and (C)

Description : Means for giving direction to the circulation of gases in furnaces are (A) Fans (B) Arrangement of heating stock in the furnaces (C) Location of outlet ports and heating & combustion devices (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Pulverised fuel fired furnaces employ __________ fuel firing. (A) Horizontal (B) Vertical (C) Tangential (D) All (A), (B) and (C)

Description : Pulverised fuel fired furnaces employ __________ fuel firing. (A) Horizontal (B) Vertical (C) Tangential (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

In which of the following furnaces, the gases are sucked through the stock bed from below? (A) Soaking pit (B) Sintering machine (C) Beehive oven (D) None of these

Description : In which of the following furnaces, the gases are sucked through the stock bed from below? (A) Soaking pit (B) Sintering machine (C) Beehive oven (D) None of these

Last Answer : (B) Sintering machine

Naphthalene recovered from coke oven gas is used (A) As moisture proof coating on fibres(B) As moth balls (insecticides)(C) As a fuel in furnaces(D) For making electrodes

Description : Naphthalene recovered from coke oven gas is used (A) As moisture proof coating on fibres (B) As moth balls (insecticides) (C) As a fuel in furnaces (D) For making electrodes

Last Answer : (C) As a fuel in furnaces

Coal is pulverised before burning in large capacity boiler furnaces mainly to (A) Ensure its complete combustion (B) Facilitate easy ash removal (C) Enhance its calorific value (D) Provide trouble free operation

Description : Coal is pulverised before burning in large capacity boiler furnaces mainly to (A) Ensure its complete combustion (B) Facilitate easy ash removal (C) Enhance its calorific value (D) Provide trouble free operation

Last Answer : (A) Ensure its complete combustion

Pig iron is produced by blast furnaces in India using mostly the iron ore named (A) Hematite (B) Magnetite (C) Siderite (D) Chalcopyrite

Description : Pig iron is produced by blast furnaces in India using mostly the iron ore named (A) Hematite (B) Magnetite (C) Siderite (D) Chalcopyrite

Last Answer : (A) Hematite

The silica is used for preparing (A) Silica bricks (B) Coke oven (C) Lining for glass furnaces (D) All of these

Description : The silica is used for preparing (A) Silica bricks (B) Coke oven (C) Lining for glass furnaces (D) All of these

Last Answer : Answer: Option D

Which of the following bricks are used for lining of furnaces? (A) Over-burnt bricks (B) Under-burnt bricks (C) Refractory bricks (D) First class bricks

Description : Which of the following bricks are used for lining of furnaces? (A) Over-burnt bricks (B) Under-burnt bricks (C) Refractory bricks (D) First class bricks

Last Answer : Answer: Option C

Regenerator is widely used in: a) Reheating Furnaces b) heat treatment furnaces c) Baking Ovens d) glass melting furnaces

Description : Regenerator is widely used in: a) Reheating Furnaces b) heat treatment furnaces c) Baking Ovens d) glass melting furnaces

Last Answer : glass melting furnaces

Is there any way to slow coke formation in ethylene furnaces?

Description : Is there any way to slow coke formation in ethylene furnaces?

Last Answer : Westaim Corporation has a commercial process for applying a special coating to the tubes used in ethylene furnaces. Westaim claims that coke buildup is reduced to one-forth to one-tenth of the ... then heat-treated and reacted with an unspecified gas. Welds cannot be coated with this process.

Electric resistance seam welding uses_______ electrodes.

Description : Electric resistance seam welding uses_______ electrodes.(A) pointed (B) disc (C) flat (D) domed

Last Answer : Electric resistance seam welding uses disc electrodes.

_________is a form of non-volatile storage that operates by changing the resistance of a specially formulated solid dielectric material. A. VRAM B. WRAM C. MRAM D. RRAM

Description : _________is a form of non-volatile storage that operates by changing the resistance of a specially formulated solid dielectric material. A. VRAM B. WRAM C. MRAM D. RRAM

Last Answer : D. RRAM Resistive RAM

The speed of a squirrel-cage, multi-speed, induction motor, as used aboard ship, is varied by changing the __________. A. number of connected poles in the stator B. frequency to the motor C. excitation voltage D. resistance of the rotor circuit

Description : The speed of a squirrel-cage, multi-speed, induction motor, as used aboard ship, is varied by changing the __________. A. number of connected poles in the stator B. frequency to the motor C. excitation voltage D. resistance of the rotor circuit

Last Answer : Answer: A

The speed of a squirrel-cage motor is usually changed by _____________. A. varying the frequency to the machine B. adding resistance in series with the stator windings C. adding resistance in parallel with the stator windings D. changing the number of connected poles in the stator

Description : The speed of a squirrel-cage motor is usually changed by _____________. A. varying the frequency to the machine B. adding resistance in series with the stator windings C. adding resistance in parallel with the stator windings D. changing the number of connected poles in the stator

Last Answer : Answer: D

An AC circuit has capacitance arranged in series. If the line voltage remains constant, the capacitive reactance value can be varied by changing the _____________. A. line frequency B. resistance C. number of commutating poles D. number of interpoles

Description : An AC circuit has capacitance arranged in series. If the line voltage remains constant, the capacitive reactance value can be varied by changing the _____________. A. line frequency B. resistance C. number of commutating poles D. number of interpoles

Last Answer : Answer: A

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

Description : 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

Last Answer : Answer: B

A degree of control over the speed of a slip ring induction motor can be obtained by _____________. A. adjusting governor linkage B. changing the number of phases to the motor C. inserting resistance into the stator circuit D. inserting resistance into the rotor circuit

Description : A degree of control over the speed of a slip ring induction motor can be obtained by _____________. A. adjusting governor linkage B. changing the number of phases to the motor C. inserting resistance into the stator circuit D. inserting resistance into the rotor circuit

Last Answer : Answer: D

Explain speed control method of 3 phase induction motor by the following methods: (1) Pole changing (2) Rotor resistance control (3) Stator voltage

Description : Explain speed control method of 3 phase induction motor by the following methods: (1) Pole changing (2) Rotor resistance control (3) Stator voltage

Last Answer : 1) Pole Changing Method:  Synchronous speed is given by, From the above equation of synchronous speed, it can be seen that synchronous speed (and hence, running speed) can ... in voltage and consequently the speed decreases and vice versa. Ultimately speed depends on the supply voltage.

In an interphase mass transfer process, the lesser the solubility of a given solute in a liquid, the higher are the chances that the transfer process will be (A) Liquid phase resistance-controlled (B) Gas phase resistance controlled (C) Impossible (D) Driven by a non-linear driving forc

Description : In an interphase mass transfer process, the lesser the solubility of a given solute in a liquid, the higher are the chances that the transfer process will be (A) Liquid phase resistance-controlled (B) Gas phase resistance controlled (C) Impossible (D) Driven by a non-linear driving forc

Last Answer : (B) Gas phase resistance controlled

Pick out the wrong statement. (A) Mechanical agitation is required, if the system has low interfacial tension (B) Sieve tray towers are generally used for systems having low interfacial tension (C) When Henry's law constant is very small, then the mass transfer rate is controlled by the gas film resistance (D) Taylor-Prandtl analogy for heat and mass transfer considers the transfer through both laminar and turbulent layers

Description : Pick out the wrong statement. (A) Mechanical agitation is required, if the system has low interfacial tension (B) Sieve tray towers are generally used for systems having low ... Prandtl analogy for heat and mass transfer considers the transfer through both laminar and turbulent layers

Last Answer : (A) Mechanical agitation is required, if the system has low interfacial tension

Which of the following is one characteristic of children having authoritarian parents? a. They are cheerful and happy b. They cope well with stress c. They show passive resistance d. They are self-controlled

Description : Which of the following is one characteristic of children having authoritarian parents? a. They are cheerful and happy b. They cope well with stress c. They show passive resistance d. They are self-controlled

Last Answer : c. They show passive resistance

A three phase slip ring induction motor with chopper controlled resistance has its torque

Description : A three phase slip ring induction motor with chopper controlled resistance has its torque proportional to   (a) Rotor current (b) Stator resistance (c) Square of rotor current (d) Square root of rotor current 

Last Answer : A three phase slip ring induction motor with chopper controlled resistance has its torque proportional to Square of rotor current

In the heating process of ______ type a simple method of temperature control is possible by means of a ...

Description : In the heating process of ______ type a simple method of temperature control is possible by means of a special alloy which loses its magnetic properties at a particular high temperature and regains ... (B) core type induction furnace (C) coreless induction furnace (D) high frequency eddy current

Last Answer : In the heating process of high frequency eddy current type a simple method of temperature control is possible by means of a special alloy which loses its magnetic properties at a particular high temperature and regains them when cooled to a temperature below this value. 

Electric ovens using heating elements made of can produce a temperature up to 3000°C.

Description : Electric ovens using heating elements made of _________can produce a temperature up to 3000°C. (A) nickel (B) graphite (C) chromium (D) iron

Last Answer : Electric ovens using heating elements made of chromium can produce a temperature up to 3000°C.