IOAA 2013, Отборен тур, хоризонтални въпроси — Задача 7. G

IOAA 2013 — Team Competition: Horizontal questions · 17 т.

Условие

i. Bode’s Galaxy is M_. [2 т.]

ii. Cigar Galaxy is M_. [2 т.]

iii. How many times fainter will a star become if its magnitude is increased by 1mag? (three decimals) [4 т.]

iv. A Globular Cluster near the nostril of Pegasus is M_. [2 т.]

v. Hipparchus described a Solar Eclipse which was seen as Total in the Hellespont (40° 25’N, 29° 43’E) but Partial in Alexandria (31° 12’N, 29° 55’E), where at maximum 4/5 of the Sun was hidden. Hipparchus calculated the parallax of the limb of the Moon between the Hellespont and Alexandria, assuming that the parallax of the Sun is 0. He also knew that the Moon has the same apparent angular diameter as the Sun, with a value of 1/650 of the circle. Finally, by applying simple trigonometry, he calculated the approximate distance between the Earth and the Moon in Earth radii. How many Earth radii is the Earth-Moon distance? (integer) [2 т.]

vi. Chandrayan-1, Deep Impact, Planck Telescope, Hubble Space Telescope [4 т.]

vii. If the mass of a star is 5 solar masses, and its initial radius and rotation period is $21x10^{5}km$ and 4.083 days respectively, how many microseconds will be its period when it turns into a Pulsar with a radius of 10km? Assume the star is a homogenous sphere and does not lose mass. [1 т.]

Отговори

Решение

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Оригинал в Архива: Horizontal_questions.pdf