Heat Radiation MCQs

Welcome to our comprehensive collection of Multiple Choice Questions (MCQs) on Heat Radiation, a fundamental topic in the field of Heat Transfer. Whether you're preparing for competitive exams, honing your problem-solving skills, or simply looking to enhance your abilities in this field, our Heat Radiation MCQs are designed to help you grasp the core concepts and excel in solving problems.

In this section, you'll find a wide range of Heat Radiation mcq questions that explore various aspects of Heat Radiation problems. Each MCQ is crafted to challenge your understanding of Heat Radiation principles, enabling you to refine your problem-solving techniques. Whether you're a student aiming to ace Heat Transfer tests, a job seeker preparing for interviews, or someone simply interested in sharpening their skills, our Heat Radiation MCQs are your pathway to success in mastering this essential Heat Transfer topic.

Note: Each of the following question comes with multiple answer choices. Select the most appropriate option and test your understanding of Heat Radiation. You can click on an option to test your knowledge before viewing the solution for a MCQ. Happy learning!

So, are you ready to put your Heat Radiation knowledge to the test? Let's get started with our carefully curated MCQs!

Heat Radiation MCQs | Page 12 of 21

Discover more Topics under Heat Transfer

Q111.
Engineering problems of practical interest are involved with heat exchange between two or more surfaces, and this exchange is strongly dependent upon

(i) Radiative properties

(ii) Temperature levels

(iii) Surface geometrics

Identify the correct statements

a.

1 and 2

b.

1 and 3

c.

2 and 3

d.

1, 2 and 3

Discuss
Answer: (d).1, 2 and 3
Q112.
The fraction of the radiative energy that is diffused from one surface element and strikes the other surface directly with no intervening reflections is called

(i) Radiation shape factor

(ii) Geometrical factor

(iii) Configuration factor

Choose the correct answer

a.

1 only

b.

2 only

c.

1, 2 and 3

d.

3 only

Discuss
Answer: (c).1, 2 and 3
Q113.
The interchange factor is also known as

a.

Equivalent emissivity

b.

Irradiation

c.

Radiosity

d.

Shape factor

Discuss
Answer: (a).Equivalent emissivity
Q114.
For the same type of shapes, the value of radiation shape factor will be higher when

a.

Surfaces are closer

b.

Surfaces are larger and held closer

c.

Surfaces are moved further apart

d.

Surfaces are smaller and held closer

Discuss
Answer: (b).Surfaces are larger and held closer
Q115.
A thin shield of emissivity E3 on both sides is placed between two infinite parallel plates of emissivities E1 and E2 and temperatures T1 and T2. If E1 = E2 = E3, then the fraction radiant energy transfer without shield takes the value

a.

0.25

b.

0.50

c.

0.75

d.

1.25

Discuss
Answer: (b).0.50
Q116.
The grey body shape factor for radiant heat exchange between a small body (emissivity = 0.4) in a large enclosure (emissivity = 0.5) is

a.

0.1

b.

0.2

c.

0.4

d.

0.5

Discuss
Answer: (c).0.4
Q117.
Two long parallel surfaces, each of emissivity 0.7 are at different temperatures and accordingly have radiation exchange between them. It is desired to reduce 75% of this radiant heat transfer by inserting thin parallel shields of equal emissivity 0.7 on both sides. What should be the number of shields?

a.

2

b.

4

c.

1

d.

3

Discuss
Answer: (d).3
Q118.
An enclosure consists of four surfaces 1, 2, 3 and 4. The view factors for radiation heat transfers are

F 11 = 0.1

F 12 = 0.4

F 13 = 0.25

The surface areas A 1 and A 2 are 4 m² and 2 m². The view factor F 41 is

a.

0.50

b.

0.75

c.

0.1

d.

0.25

Discuss
Answer: (a).0.50
Q119.
The value of shape factor depends on how many factors?

a.

4

b.

1

c.

2

d.

3

Discuss
Answer: (c).2
Q120.
A large plane, perfectly insulated on one face and maintained at a fixed temperature T 1 on the bare face, has an emissivity of 0.84 and loses 250 W/m² when exposed to surroundings at nearly 0 K. The radiant heat loss from another plane of the same size is 125 W/m² when bare face having emissivity 0.42 and is maintained at temperature T 2 is exposed to the same surroundings. Subsequently these two planes are brought together so that the parallel bare faces lie only 1 cm apart and the heat supply to each is so regulated that their respective temperatures T 1 and T 2 remains unchanged. Determine he net heat flux between the planes

a.

0

b.

1

c.

2

d.

3

Discuss
Answer: (a).0
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