The amount of radiation mainly depends upon the

Question

The amount of radiation mainly depends upon the

A. Nature of the body

B. Temperature of the body

C. Type of surface of the body

D. All of these

Share this question with your friends

Show all Heat & Mass Transfer MCQ

Comment

Depending on the radiating properties, body will be transparent when

A. P = 0, x = 0 and a = 1

B. P=1, x = 0, and a = 0

C. P = 0, T= 1, and a = 0

D. X = 0, a + p = 1

Discuss this answer

The insulation ability of an insulator with the presence of moisture would

A. Increase

B. Decrease

C. Remain unaffected

D. May increase/decrease depending on temperature and thickness of insulation

Discuss this answer

The thermal diffusivities for gases are generally

A. More than those for liquids

B. Less than those for liquids

C. More than those for solids

D. Dependent on the viscosity

Discuss this answer

In a shell and tube heat exchanger, baffles are provided on the shell side to

A. Improve heat transfer

B. Provide support for tubes

C. Prevent stagnation of shell side fluid

D. All of these

Discuss this answer

A perfect black body is one which

A. Is black in colour

B. Reflects all heat

C. Transmits all heat radiations

D. Absorbs heat radiations of all wave lengths falling on it

Discuss this answer

Radiation is the process of heat transfer in which heat flows from a ________, in a straight line, without affecting the intervening medium.

A. Cold body to hot body

B. Hot body to cold body

C. Smaller body to larger body

D. Larger body to smaller body

Discuss this answer

Two balls of same material and finish have their diameters in the ratio of 2: 1 and both are heated to same temperature and allowed to cool by radiation. Rate of cooling by big ball as compared to smaller one will be in the ratio of

A. 1 : 1

B. 2 : 1

C. 1 : 2

D. 4 : 1

Discuss this answer

Unit of thermal conductivity in M.K.S. units is

A. K cal/kg m² °C

B. K cal m/hr m² °C

C. K cal/hr m² °C

D. K calm/hr °C

Discuss this answer

Thermal conductivity of water in general with rise in temperature

A. Increases

B. Decreases

C. Remain constant

D. May increase or decrease depending on temperature

Discuss this answer

Which of the following has least value of conductivity?

A. Glass

B. Water

C. Plastic

D. Air

Discuss this answer

The rate of energy emission from unit surface area through unit solid angle, along a normal to the surface, is known as

A. Emissivity

B. Transmissivity

C. Reflectivity

D. Intensity of radiation

Discuss this answer

When heat is transferred by molecular collision, it is referred to as heat transfer by

A. Conduction

B. Convection

C. Radiation

D. Scattering

Discuss this answer

Depending on the radiating properties, a body will be opaque when

A. P = 0, x = 0 and a = 1

B. P=1, x = 0 and a = 0

C. P = 0, x = 1 and a = 0

D. X = 0, a + p = 1 Where a = absorptivity, p = reflectivity, X = transmissivity.

Discuss this answer

Conduction is a process of heat transfer

A. From one particle of the body to another without the actual motion of the particles

B. From one particle of the body to another by the actual motion of the heated particles

C. From a hot body to a cold body, in a straight line, without affecting the intervening medium

D. None of the above

Discuss this answer

The logarithmic mean temperature difference (t_m) is given by (where Δt₁ and Δt₂ are temperature differences between the hot and cold fluids at entrance and exit)

A. t_m = (Δt₁ - Δt₂)/ log_e (Δt₁/Δt₂)

B. t_m = log_e (Δt₁/Δt₂)/ (Δt₁ - Δt₂)

C. t_m = t_m = (Δt₁ - Δt₂) log_e (Δt₁/Δt₂)

D. t_m = log_e (Δt₁ - Δt₂)/ Δt₁/Δt₂

Discuss this answer

The critical temperature is the temperature

A. Below which a gas does not obey gas laws

B. Above which a gas may explode

C. Below which a gas is always liquefied

D. Above which a gas will never liquefied

Discuss this answer

The process of heat transfer from one particle of the body to another is called conduction, when the particles of the body

A. Move actually

B. Do not move actually

C. Affect the intervening medium

D. Does not affect the intervening medium

Discuss this answer

Total heat is the heat required to

A. Change vapour into liquid

B. Change liquid into vapour

C. Increase the temperature of a liquid or vapour

D. Convert water into steam and superheat it

Discuss this answer

Thermal conductivity of air with rise in temperature

A. Increases

B. Decreases

C. Remain constant

D. May increase or decrease depending on temperature

Discuss this answer

Thermal conductivity of glass wool varies from sample to sample because of variation in

A. Composition

B. Density

C. Porosity

D. All of the above

Discuss this answer

The critical thickness of insulation for a sphere is

A. k/h₀

B. 2k/h₀

C. h₀/k

D. h₀/2k

Discuss this answer

Heat is closely related with

A. Liquids

B. Energy

C. Temperature

D. Entropy

Discuss this answer

Which of the following has maximum value of thermal conductivity?

A. Aluminium

B. Steel

C. Brass

D. Copper

Discuss this answer

The product of Reynolds number and Prandtl number is known as

A. Stanton number

B. Biot number

C. Peclet number

D. Grashoff number

Discuss this answer

Film coefficient is defined as the ratio of

A. Thermal conductivity to the equivalent thickness of the film of fluid

B. Temperature drop through the films of fluids to the thickness of film of fluids

C. Thickness of film of fluid to the thermal conductivity

D. Thickness of film of fluid to the temperature drop through the films of fluids

Discuss this answer

An electric cable of aluminium conductor (k = 240 W/mK) is to be insulated with rubber (k = 0.15 W/mK). The cable is to be located in air (h = 6 W/m²). The critical thickness of insulation will be

A. 25 mm

B. 40 mm

C. 160 mm

D. 800 mm

Discuss this answer

Thermal conductivity of water ________ with rise in temperature.

A. Remain same

B. Decreases

C. Increases

D. May increase or decrease depending upon temperature

Discuss this answer

The total radiation from a black body per second per unit area is ________ fourth power of the absolute temperature. This statement is known as Stefan Boltzmann law.

A. Equal to

B. Directly proportional to

C. Inversely proportional to

D. None of these

Discuss this answer

The amount of radiation mainly depends upon the

A. Nature of the body

B. Temperature of the body

C. Type of surface of the body

D. All of these

Discuss this answer

In free convection heat transfer transition from laminar to turbulent flow is governed by the critical value of the

A. Reynold's number

B. Grashoff's number

C. Reynold's number, Grashoff's number

D. Prandtl number, Grashoff's number

Discuss this answer

Accepted Answer

D. All of these

The amount of radiation mainly depends upon the

Correct Answer :

Show all Heat & Mass Transfer MCQ

Related Questions

Depending on the radiating properties, body will be transparent when

The insulation ability of an insulator with the presence of moisture would

The thermal diffusivities for gases are generally

In a shell and tube heat exchanger, baffles are provided on the shell side to

A perfect black body is one which

Radiation is the process of heat transfer in which heat flows from a ________, in a straight line, without affecting the intervening medium.

Two balls of same material and finish have their diameters in the ratio of 2: 1 and both are heated to same temperature and allowed to cool by radiation. Rate of cooling by big ball as compared to smaller one will be in the ratio of

Unit of thermal conductivity in M.K.S. units is

Thermal conductivity of water in general with rise in temperature

Which of the following has least value of conductivity?

The rate of energy emission from unit surface area through unit solid angle, along a normal to the surface, is known as

When heat is transferred by molecular collision, it is referred to as heat transfer by

Depending on the radiating properties, a body will be opaque when

Conduction is a process of heat transfer

The logarithmic mean temperature difference (t_m) is given by (where Δt₁ and Δt₂ are temperature differences between the hot and cold fluids at entrance and exit)

The critical temperature is the temperature

The process of heat transfer from one particle of the body to another is called conduction, when the particles of the body

Total heat is the heat required to

Thermal conductivity of air with rise in temperature

Thermal conductivity of glass wool varies from sample to sample because of variation in

The critical thickness of insulation for a sphere is

Heat is closely related with

Which of the following has maximum value of thermal conductivity?

The product of Reynolds number and Prandtl number is known as

Film coefficient is defined as the ratio of

An electric cable of aluminium conductor (k = 240 W/mK) is to be insulated with rubber (k = 0.15 W/mK). The cable is to be located in air (h = 6 W/m²). The critical thickness of insulation will be

Thermal conductivity of water ________ with rise in temperature.

The total radiation from a black body per second per unit area is ________ fourth power of the absolute temperature. This statement is known as Stefan Boltzmann law.

The amount of radiation mainly depends upon the

In free convection heat transfer transition from laminar to turbulent flow is governed by the critical value of the

Also checkout

The amount of radiation mainly depends upon the

Correct Answer :

Show all Heat & Mass Transfer MCQ

Related Questions

Depending on the radiating properties, body will be transparent when

The insulation ability of an insulator with the presence of moisture would

The thermal diffusivities for gases are generally

In a shell and tube heat exchanger, baffles are provided on the shell side to

A perfect black body is one which

Radiation is the process of heat transfer in which heat flows from a ________, in a straight line, without affecting the intervening medium.

Two balls of same material and finish have their diameters in the ratio of 2: 1 and both are heated to same temperature and allowed to cool by radiation. Rate of cooling by big ball as compared to smaller one will be in the ratio of

Unit of thermal conductivity in M.K.S. units is

Thermal conductivity of water in general with rise in temperature

Which of the following has least value of conductivity?

The rate of energy emission from unit surface area through unit solid angle, along a normal to the surface, is known as

When heat is transferred by molecular collision, it is referred to as heat transfer by

Depending on the radiating properties, a body will be opaque when

Conduction is a process of heat transfer

The logarithmic mean temperature difference (tm) is given by (where Δt1 and Δt2 are temperature differences between the hot and cold fluids at entrance and exit)

The critical temperature is the temperature

The process of heat transfer from one particle of the body to another is called conduction, when the particles of the body

Total heat is the heat required to

Thermal conductivity of air with rise in temperature

Thermal conductivity of glass wool varies from sample to sample because of variation in

The critical thickness of insulation for a sphere is

Heat is closely related with

Which of the following has maximum value of thermal conductivity?

The product of Reynolds number and Prandtl number is known as

Film coefficient is defined as the ratio of

An electric cable of aluminium conductor (k = 240 W/mK) is to be insulated with rubber (k = 0.15 W/mK). The cable is to be located in air (h = 6 W/m²). The critical thickness of insulation will be

Thermal conductivity of water ________ with rise in temperature.

The total radiation from a black body per second per unit area is ________ fourth power of the absolute temperature. This statement is known as Stefan Boltzmann law.

The amount of radiation mainly depends upon the

In free convection heat transfer transition from laminar to turbulent flow is governed by the critical value of the

Also checkout

The logarithmic mean temperature difference (t_m) is given by (where Δt₁ and Δt₂ are temperature differences between the hot and cold fluids at entrance and exit)