Heat Transfer Archives - Page 18 of 57 -

Question: Fourier’s law of heat conduction is (where Q = Amount of heat flow through the body in unit time, A = Surface area of heat flow, taken at right angles to the direction of heat flow, dT = Temperature difference on the two faces of the body, dx = Thickness of the body, through which the heat flows, taken along the direction of heat flow, and k = Thermal conductivity of the body)
[A].

[B].

[C].

[D].

Answer: Option A

Explanation:

No answer description available for this question.

Fourier’s law of heat conduction is (where Q = Amount of heat flow through the body in unit time, A = Surface area of heat flow, taken at right angles to the direction of heat flow, dT = Temperature difference on the two faces of the body, dx = Thickness of the body, through which the heat flows, taken along the direction of heat flow, and k = Thermal conductivity of the body) Read More »

Heat Transfer, Mechanical Engineering, Refrigeration and Air Conditioning

In case of liquids and gases, the heat transfer takes place according to

Heat Transfer, Mechanical Engineering, Refrigeration and Air Conditioning / admin

Question: In case of liquids and gases, the heat transfer takes place according to
[A].

conduction

[B].

convection

[C].

radiation

[D].

none of these

Answer: Option B

Explanation:

No answer description available for this question.

In case of liquids and gases, the heat transfer takes place according to Read More »

Heat Transfer, Mechanical Engineering, Refrigeration and Air Conditioning

In case of solids, the heat transfer takes place according to radiation.

Heat Transfer, Mechanical Engineering, Refrigeration and Air Conditioning / admin

Question: In case of solids, the heat transfer takes place according to radiation.
[A].

Correct

[B].

Incorrect

Answer: Option B

Explanation:

No answer description available for this question.

In case of solids, the heat transfer takes place according to radiation. Read More »

Heat Transfer, Mechanical Engineering, Refrigeration and Air Conditioning

Conduction is the process of heat transfer from one particle of the body to another by the actual motion of the heated particles.

Heat Transfer, Mechanical Engineering, Refrigeration and Air Conditioning / admin

Question: Conduction is the process of heat transfer from one particle of the body to another by the actual motion of the heated particles.
[A].

True

[B].

False

Answer: Option B

Explanation:

No answer description available for this question.

Conduction is the process of heat transfer from one particle of the body to another by the actual motion of the heated particles. Read More »

Heat Transfer, Mechanical Engineering, Refrigeration and Air Conditioning

Conduction is a process of heat transfer

Heat Transfer, Mechanical Engineering, Refrigeration and Air Conditioning / admin

Question: 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

Answer: Option A

Explanation:

No answer description available for this question.

Conduction is a process of heat transfer Read More »

Heat Transfer, Mechanical Engineering, Refrigeration and Air Conditioning

In Joule’s experiment, an insulated container contains 20 kg of water initially at 25°C. It is stirred by an agitator, which is made to turn by a slowly falling body weighing 40 kg through a height of 4 m. The process is repeated 500 times. The acceleration due to gravity is 9.8 ms-2. Neglecting the heat capacity of agitator, the temperature of water (in °C) is

CHEMICAL ENGINEERING, Heat Transfer / admin

Question: In Joule’s experiment, an insulated container contains 20 kg of water initially at 25°C. It is stirred by an agitator, which is made to turn by a slowly falling body weighing 40 kg through a height of 4 m. The process is repeated 500 times. The acceleration due to gravity is 9.8 ms-2. Neglecting the heat capacity of agitator, the temperature of water (in °C) is
[A].

40.5

[B].

34.4

[C].

26.8

[D].

Answer: Option B

Explanation:

No answer description available for this question.

In Joule’s experiment, an insulated container contains 20 kg of water initially at 25°C. It is stirred by an agitator, which is made to turn by a slowly falling body weighing 40 kg through a height of 4 m. The process is repeated 500 times. The acceleration due to gravity is 9.8 ms-2. Neglecting the heat capacity of agitator, the temperature of water (in °C) is Read More »

CHEMICAL ENGINEERING, Heat Transfer

A long iron rod initially at a temperature of 20°C has one end dipped in boiling water (100°C) at time, t = 0. The curved surface of the rod is insulated so that heat conduction is one dimensional in the axial direction. The temperature at a distance 100 mm from the dipped end becomes 40°C at time, t = 200 s. The same temperature is achieved at a distance of 200 mm from the dipped end at time

CHEMICAL ENGINEERING, Heat Transfer / admin

Question: A long iron rod initially at a temperature of 20°C has one end dipped in boiling water (100°C) at time, t = 0. The curved surface of the rod is insulated so that heat conduction is one dimensional in the axial direction. The temperature at a distance 100 mm from the dipped end becomes 40°C at time, t = 200 s. The same temperature is achieved at a distance of 200 mm from the dipped end at time
[A].

t = 283 s

[B].

t = 356 s

[C].

t = 400 s

[D].

t = 800 s

Answer: Option D

Explanation:

No answer description available for this question.

A long iron rod initially at a temperature of 20°C has one end dipped in boiling water (100°C) at time, t = 0. The curved surface of the rod is insulated so that heat conduction is one dimensional in the axial direction. The temperature at a distance 100 mm from the dipped end becomes 40°C at time, t = 200 s. The same temperature is achieved at a distance of 200 mm from the dipped end at time Read More »

CHEMICAL ENGINEERING, Heat Transfer

A composite wall consists of two plates A and B placed in series normal to the flow of heat. The thermal conductivities are kA and kB and the specific heat capacities are CPA and CPB for plates A and B respectively. Plate B has twice the thickness of plate A. At steady state, the temperature difference across plate A is greater than that across plate B, when

CHEMICAL ENGINEERING, Heat Transfer / admin

Question: A composite wall consists of two plates A and B placed in series normal to the flow of heat. The thermal conductivities are kA and kB and the specific heat capacities are CPA and CPB for plates A and B respectively. Plate B has twice the thickness of plate A. At steady state, the temperature difference across plate A is greater than that across plate B, when
[A].

CPA > CPB

[B].

CPA < CPB

[C].

kA < 0.5kB

[D].

kA>2 kB

Answer: Option C

Explanation:

No answer description available for this question.

A composite wall consists of two plates A and B placed in series normal to the flow of heat. The thermal conductivities are kA and kB and the specific heat capacities are CPA and CPB for plates A and B respectively. Plate B has twice the thickness of plate A. At steady state, the temperature difference across plate A is greater than that across plate B, when Read More »

CHEMICAL ENGINEERING, Heat Transfer

Fresh orange juice contains 12% (by weight) solids and the rest water 90% of the fresh juice is sent to an evaporator to remove water and subsequently mixed with the remaining 10% of fresh juice. The resultant product contains 40% solids. The kg of water removed from 1 kg fresh juice is

CHEMICAL ENGINEERING, Heat Transfer / admin

Question: Fresh orange juice contains 12% (by weight) solids and the rest water 90% of the fresh juice is sent to an evaporator to remove water and subsequently mixed with the remaining 10% of fresh juice. The resultant product contains 40% solids. The kg of water removed from 1 kg fresh juice is
[A].

0.4

[B].

0.5

[C].

0.6

[D].

0.7

Answer: Option D

Explanation:

No answer description available for this question.

Fresh orange juice contains 12% (by weight) solids and the rest water 90% of the fresh juice is sent to an evaporator to remove water and subsequently mixed with the remaining 10% of fresh juice. The resultant product contains 40% solids. The kg of water removed from 1 kg fresh juice is Read More »

CHEMICAL ENGINEERING, Heat Transfer