IOAA Jr. 2022, Теория, тест с избираем отговор — Задача 10. The luminosity of a star

International Olympiad of Astronomy and Space Sciences for Juniors — Romania– Câmpulung Moldovenesc — October 31 - November 7 2022 — Theoretical Round — I. Multiple choice problems – 100 points · 31 октомври 2022 г.

I. Multiple choice problems – 100 points

For these problems, you have to choose only one correct answer. Please write your answer on answer-sheet. Don’t forget to write the number of the problem, i.e Grid 1. (c).

Условие

The luminosity of a star $\Sigma$, is $L_\Sigma = 100 \cdot L_S$, where $L_S$ is the luminosity of the Sun, and the star’s surface temperature is $T_\Sigma = \frac{1}{2} \cdot T_S$, where $T_S$ is the Sun’s surface temperature.

Ratio between the radius of the star and the radius of the Sun is:

a) $\dfrac{R_\Sigma}{R_{\mathrm{S}}} = 40$;

b) $\dfrac{R_\Sigma}{R_{\mathrm{S}}} = 30$;

c) $\dfrac{R_\Sigma}{R_{\mathrm{S}}} = 60$;

d) $\dfrac{R_\Sigma}{R_{\mathrm{S}}} = 50$.

Отговори

Решение

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Оригинал в Архива: Multiple_Choice.pdf · официални решения: Grid_1.pdf · допълнителни данни: Grid_2.pdf · допълнителни данни: Grid_3.pdf · допълнителни данни: Grid_4.pdf · допълнителни данни: Grid_5.pdf · допълнителни данни: Grid_6.pdf · допълнителни данни: Grid_7.pdf · допълнителни данни: Grid_8.pdf · допълнителни данни: Grid_9.pdf · допълнителни данни: Grid_10.pdf