A star emits visible light. If it gets hotter while staying at the same size, it becomes
Group of answer choices
more luminous and redder.
whiter
less luminous and bluer.
more luminous and bluer.
less luminous and redder.
more luminous and bluer.
To answer this question, we need to understand a few concepts related to the behavior of stars.
When a star heats up, its temperature increases. As the temperature of a star increases, its color changes. The color of a star is an indication of its temperature, with hotter stars appearing bluer and cooler stars appearing redder. This relationship between temperature and color is known as the stellar spectral classification.
Additionally, the luminosity of a star refers to its total amount of energy emitted per unit time. It depends on several factors, including the star's surface area and temperature. Generally, as a star gets hotter, its luminosity tends to increase.
Now, if we consider the given options:
- "More luminous and redder." This option is incorrect because, according to our understanding of the relationship between temperature and color, a hotter star would appear bluer rather than redder.
- "Whiter." This option is incorrect because, as stated earlier, the color of a star depends on its temperature. A hotter star would not appear whiter; it would appear bluer.
- "Less luminous and bluer." This option is incorrect as well. When a star gets hotter, it tends to become more luminous, not less.
- "More luminous and bluer." This option is correct. As a star gets hotter while maintaining the same size, it becomes more luminous and bluer in color. This is in accordance with the behavior of stars discussed above.
- "Less luminous and redder." This option is incorrect for the same reasons mentioned previously. A hotter star would not appear redder; it would appear bluer.
Therefore, the correct answer is "More luminous and bluer."