Let us assume that our galaxy consists of 2.5 × 10¹¹ stars each of one solar mass. How long will a star at a distance of 50,000 ly from the galactic centre take to complete one revolution? Take the diameter of the Milky Way to be 10⁵ ly.

Open in App

Solution

Mass of our galaxyMilky Way, M = 2.5 × 10¹¹ solar mass
Solar mass = Mass ofSun = 2.0 × 10³⁶kg
Mass of our galaxy, M= 2.5 × 10¹¹ ×2 × 10³⁶ = 5×10⁴¹ kg
Diameter of Milky Way,d = 10⁵ ly
Radius of Milky Way, r= 5 × 10⁴ ly
1 ly = 9.46 ×10¹⁵ m
∴r = 5 ×10⁴ × 9.46 ×10¹⁵
=4.73 ×10²⁰ m
Since a star revolvesaround the galactic centre of the Milky Way, its time period is givenby the relation:

Suggest Corrections

Similar questions

Q. Let us assume that our galaxy consists of

2.5 \times 10^{11}

stars each of one solar mass. How long will a star at a distance of 50,000 ly from the galactic centre take to complete one revolution ? Take the diameter of the Milky Way to be

10^{5}

ly.

In heaven,God uses star mass unit(smu) to measure weight of galaxies . 1 smu = 1/30th of the mass of the star.If the mass of our milky way galaxy is 900 smu, mass of how many stars will be equal to the mass of milky way galaxy?

Q. The Milky Way is the galaxy that contains our solar system. The solar system is located within the disc, about

27, 000

light years from the Galactic Centre, on the inner edge of one of the spiral-shaped concentrations of gas and dust called the ________ arm.

Our milky way galaxy consists of millions of stars that make it more shiny in the black sky. Which powerful source of energy has turned The Identity of Milky Way into a huge Galaxy consisting of all the all the celestial bodies on a proper place with proper atmosphere.

Q. Search and you will find.
a. Our galaxy is called..................
b. For measuring large distances.................... is used as a unit.
c. The speed of light is .................. km/s
d. There are about ................ stars in our galaxy.
e. The end stage of the sun will be .....................
f. Stars are born out of ............... clouds.
g. Milky way is a .............. galaxy.
h. Stars are spheres of ................. gas.
i. The masses of other stars are measured relative to the mass of the ..................
j. Light takes ........................... to reach us from the moon.
k. The larger the mass of a star the faster is its.................
l. The number of fuels used in the life of a star depends on its .......................

Join BYJU'S Learning Program

Let us assume that our galaxy consists of 2.5 × 1011 stars each of one solar mass. How long will a star at a distance of 50,000 ly from the galactic centre take to complete one revolution? Take the diameter of the Milky Way to be 105 ly.

Let us assume that our galaxy consists of 2.5 × 10¹¹ stars each of one solar mass. How long will a star at a distance of 50,000 ly from the galactic centre take to complete one revolution? Take the diameter of the Milky Way to be 10⁵ ly.