Concept explainers
Which of the following is luminous?
a. Moon
b. Mars
c. Sun
d. All of the above
The luminous body from the following options.
Moon
Mars
Sun
All of the above
Answer to Problem 1AC
Solution:
Option (c) is correct.
Explanation of Solution
Introduction:
A body is said to be a luminous body if it emits or radiate light on its own. They produce their own light from their own source of energy. Example: Sun is a luminous body.
Explanation:
Reason for the correct option:
Since the sun produces its own light by the help of nuclear fusion reactions which converts hydrogen to helium with a liberation of enormous amount of energy and light. This makes sun a luminous body.
Hence, option (c) is correct.
Reason for the incorrect options:
Option (a) is incorrect becausemoon takes light from the sun and reflects it and is visible to us. It doesn’t produce light of its own. So it is not luminous. Hence, it is a wrong answer.
Option (b) is incorrect because Mars also takes light from sun and reflects. So it is non-luminous. Hence, it is a wrong answer.
Option (d) is incorrect because option (c) is correct. So it can’t be the answer.
Hence, options (a), (b) and (d) are incorrect.
Conclusion:
Among the given options, only Sun is luminous.
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Chapter 7 Solutions
Physical Science (12th Edition), Standalone Book
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