When the cross-section of a nozzle __________ continuously from entrance to exit, it is called a convergent nozzle.

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When the cross-section of a nozzle __________ continuously from entrance to exit, it is called a convergent nozzle.

A. Increases

B. Decreases

C. Remain same

D. None of these

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The draught (in mm of water), for maximum discharge of flue gases through the chimney, is given by (where H = Height of the chimney in metres, and T₁ = Absolute temperature of air outside the chimney in K)

A. T₁ /88.25H

B. 88.25H/T₁

C. T₁ /176.5H

D. 176.5H/T₁

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In a 50% reaction turbine stage, tangential component of absolute velocity at rotor inlet is 537 m/s and the blade velocity is 454 m/s. The power output in kW of steam will be

A. 260 kW

B. 282 kW

C. 296 kW

D. 302 kW

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The fittings mounted on the boiler for its proper and safe functioning is a

A. Water level indicator

B. Pressure gauge

C. Safety valve

D. All of these

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Which of the following compound steam engine requires a smaller flywheel?

A. Receiver type

B. Tandem type

C. Woolf type

D. All of these

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Ultimate analysis of fuel is determination of percentage of

A. Carbon, hydrogen, nitrogen, sulphur, moisture

B. Fixed carbon, ash, volatile matter, moisture

C. Higher calorific value

D. Lower calorific value

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The Parsons' reaction turbine has

A. Only moving blades

B. Only fixed blades

C. Identical fixed and moving blades

D. Fixed and moving blades of different shape

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A safety valve mainly used with locomotive and marine boilers is

A. Lever safety valve

B. Dead weight safety valve

C. High steam and low water safety valve

D. Spring loaded safety valve

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There is always some steam left in the clearance space from the previous stroke. This steam left in the clearance space is called

A. Wet steam

B. Saturated steam

C. Superheated steam

D. Cushion steam

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A device in which some portion of waste heat of flue gases is recovered to heat the air before it passes to the furnace for combustion purpose, is known as

A. Superheater

B. Air-preheater

C. Economiser

D. Injector

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An impulse turbine as compared to a reaction turbine, for a given power has _________ row of blades.

A. Equal

B. Less

C. More

D. None of these

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When the cross-section of a nozzle increases continuously from entrance to exit, it is called a

A. Divergent nozzle

B. Convergent nozzle

C. Convergent-divergent nozzle

D. None of these

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In water tube boilers

A. Water passes through the tubes which are surrounded by flames and hot gases

B. The flames and hot gases pass through the tubes which are surrounded by water

C. Forced circulation takes place

D. None of these

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Degree of reaction is defined as the ratio of

A. Heat drop in fixed blades to the heat drop in moving blades

B. Heat drop in moving blades to the heat drop in fixed blades

C. Heat drop in moving blades to the heat drop in fixed blades plus heat drop in moving blades

D. Heat drop in fixed blades plus heat drop in moving blades to the heat drop in moving blades

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The ratio of the isentropic heat drop to the heat supplied, is called

A. Reheat factor

B. Stage efficiency

C. Internal efficiency

D. Rankine efficiency

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Which of the following statement is wrong?

A. The critical pressure gives the velocity of steam at the throat equal to the velocity of sound.

B. The flow in the convergent portion of the nozzle is subsonic.

C. The flow in the divergent portion of the nozzle is supersonic.

D. To increase the velocity of steam above sonic velocity (supersonic) by expanding steam below the critical pressure, the divergent portion for the nozzle is not necessary.

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The ratio of the workdone on the blades to the energy supplied to the blades, is called

A. Blading efficiency

B. Nozzle efficiency

C. Gross or stage efficiency

D. Mechanical efficiency

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A compound steam engine in which piston rods of high pressure and low pressure cylinders are attached to two different cranks set at 90° to each other, is called

A. Receiver type compound engine

B. Tandem type compound engine

C. Woolf type compound engine

D. Both (A) and (B)

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In forced circulation steam boilers, the force is applied

A. To draw water

B. To circulate water

C. To drain off the water

D. All of these

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The device attached to the steam chest for preventing explosions due to excessive internal pressure of steam is called

A. Safety valve

B. Water level indicator

C. Pressure gauge

D. Fusible plug

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Which of the following statement is correct for steam turbines as compared to reciprocating steam engines?

A. A steam turbine develops higher speeds

B. The efficiency of steam turbine is higher

C. The steam consumption is less

D. All of these

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The artificial draught is produced by

A. Steam jet

B. Centrifugal fan

C. Chimney

D. Both (A) and (B)

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An economiser in a boiler

A. Increases steam pressure

B. Increases steam flow

C. Decreases fuel consumption

D. Decreases steam pressure

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The critical pressure ratio is given by (where p₁ = Initial pressure of steam, and p₂ = Pressure of steam at throat or critical pressure)

A. p₁. p₂

B. p₁/p₂

C. p₂/p₁

D. p₁ + p₂

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A single acting steam engine produces ________ power than that of double acting steam engine.

A. Equal

B. Half

C. Double

D. Four times

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Curtis turbine is a

A. Simple reaction turbine

B. Velocity compounded turbine

C. Pressure compounded turbine

D. Pressure-velocity compounded turbine

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The velocity of steam at throat of the nozzle is __________ the velocity of sound.

A. Equal to

B. Less than

C. More than

D. None of these

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For the same diameter and thickness of tube, a water tube boiler compared to a fire tube boiler has

A. More heating surface

B. Less heating surface

C. Equal heating surface

D. Heating surface depends on other parameters

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The fire tubes in a Cochran boiler are

A. Horizontal

B. Vertical

C. Inclined

D. None of these

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The overall efficiency of thermal power plant is

A. Boiler efficiency, turbine efficiency, generator efficiency

B. All the three above plus gas cycle efficiency

C. Carnot cycle efficiency

D. Regenerative cycle efficiency

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Orsat meter is used for

A. Gravimetric analysis of the flue gases

B. Volumetric analysis of the flue gases

C. Mass flow of the flue gases

D. Measuring smoke density of flue gases

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Accepted Answer

B. Decreases

When the cross-section of a nozzle __________ continuously from entrance to exit, it is called a convergent nozzle.

Correct Answer :

Show all Steam Boilers, Engines, Nozzles & Turbines MCQ

Related Questions

The draught (in mm of water), for maximum discharge of flue gases through the chimney, is given by (where H = Height of the chimney in metres, and T₁ = Absolute temperature of air outside the chimney in K)

In a 50% reaction turbine stage, tangential component of absolute velocity at rotor inlet is 537 m/s and the blade velocity is 454 m/s. The power output in kW of steam will be

The fittings mounted on the boiler for its proper and safe functioning is a

Which of the following compound steam engine requires a smaller flywheel?

Ultimate analysis of fuel is determination of percentage of

The Parsons' reaction turbine has

A safety valve mainly used with locomotive and marine boilers is

There is always some steam left in the clearance space from the previous stroke. This steam left in the clearance space is called

A device in which some portion of waste heat of flue gases is recovered to heat the air before it passes to the furnace for combustion purpose, is known as

An impulse turbine as compared to a reaction turbine, for a given power has _________ row of blades.

When the cross-section of a nozzle increases continuously from entrance to exit, it is called a

In water tube boilers

Degree of reaction is defined as the ratio of

The ratio of the isentropic heat drop to the heat supplied, is called

Which of the following statement is wrong?

The ratio of the workdone on the blades to the energy supplied to the blades, is called

A compound steam engine in which piston rods of high pressure and low pressure cylinders are attached to two different cranks set at 90° to each other, is called

In forced circulation steam boilers, the force is applied

The device attached to the steam chest for preventing explosions due to excessive internal pressure of steam is called

Which of the following statement is correct for steam turbines as compared to reciprocating steam engines?

The artificial draught is produced by

An economiser in a boiler

The critical pressure ratio is given by (where p₁ = Initial pressure of steam, and p₂ = Pressure of steam at throat or critical pressure)

A single acting steam engine produces ________ power than that of double acting steam engine.

Curtis turbine is a

The velocity of steam at throat of the nozzle is __________ the velocity of sound.

For the same diameter and thickness of tube, a water tube boiler compared to a fire tube boiler has

The fire tubes in a Cochran boiler are

The overall efficiency of thermal power plant is

Orsat meter is used for

Also checkout

When the cross-section of a nozzle __________ continuously from entrance to exit, it is called a convergent nozzle.

Correct Answer :

Show all Steam Boilers, Engines, Nozzles & Turbines MCQ

Related Questions

The draught (in mm of water), for maximum discharge of flue gases through the chimney, is given by (where H = Height of the chimney in metres, and T1 = Absolute temperature of air outside the chimney in K)

In a 50% reaction turbine stage, tangential component of absolute velocity at rotor inlet is 537 m/s and the blade velocity is 454 m/s. The power output in kW of steam will be

The fittings mounted on the boiler for its proper and safe functioning is a

Which of the following compound steam engine requires a smaller flywheel?

Ultimate analysis of fuel is determination of percentage of

The Parsons' reaction turbine has

A safety valve mainly used with locomotive and marine boilers is

There is always some steam left in the clearance space from the previous stroke. This steam left in the clearance space is called

A device in which some portion of waste heat of flue gases is recovered to heat the air before it passes to the furnace for combustion purpose, is known as

An impulse turbine as compared to a reaction turbine, for a given power has _________ row of blades.

When the cross-section of a nozzle increases continuously from entrance to exit, it is called a

In water tube boilers

Degree of reaction is defined as the ratio of

The ratio of the isentropic heat drop to the heat supplied, is called

Which of the following statement is wrong?

The ratio of the workdone on the blades to the energy supplied to the blades, is called

A compound steam engine in which piston rods of high pressure and low pressure cylinders are attached to two different cranks set at 90° to each other, is called

In forced circulation steam boilers, the force is applied

The device attached to the steam chest for preventing explosions due to excessive internal pressure of steam is called

Which of the following statement is correct for steam turbines as compared to reciprocating steam engines?

The artificial draught is produced by

An economiser in a boiler

The critical pressure ratio is given by (where p₁ = Initial pressure of steam, and p₂ = Pressure of steam at throat or critical pressure)

A single acting steam engine produces ________ power than that of double acting steam engine.

Curtis turbine is a

The velocity of steam at throat of the nozzle is __________ the velocity of sound.

For the same diameter and thickness of tube, a water tube boiler compared to a fire tube boiler has

The fire tubes in a Cochran boiler are

The overall efficiency of thermal power plant is

Orsat meter is used for

Also checkout

The draught (in mm of water), for maximum discharge of flue gases through the chimney, is given by (where H = Height of the chimney in metres, and T₁ = Absolute temperature of air outside the chimney in K)