Concept explainers
The correct statement
Answer to Problem 1QP
Option (b)
Explanation of Solution
Write the equation for the brightness of a star.
Here,
The distance of both the star A and star B is same from the earth. Hence, the luminosity is directly proportional to the brightness. When the brightness of the star A is halved, its luminosity will also become halved. As a result, the star B is now twice as bright as star B.
Conclusion:
Both star A and star B are nearly at same distance from the earth. The brightness of star A being halved does not have any influence on its distance from earth. Therefore option (a) is incorrect.
When the brightness of the star A is halved, its luminosity will also become. As a result, the star B is now twice as bright as star B. Therefore, option (b) is correct.
When the brightness of the star A is halved, its luminosity will also become. As a result, the star B is now twice as bright as star B and does not do anything with the hotness. Therefore, option (c) is incorrect.
The brightness of star A being halved does not anything to do with the size of the star A or star B. Therefore, option (d) is incorrect.
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Chapter 13 Solutions
21st Century Astronomy
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