Physics · Science General

Astronomy and Cosmology

4,450 Questions

This topic provides questions on astronomy, cosmology, and the physical universe. It covers subjects like the Hubble sequence, constellations, dark matter, and stellar evolution. These questions help build a strong foundation for general science exam sections.

Galaxies and clustersConstellations and starsStellar evolutionSpace observatories

Astronomy and Cosmology Questions

Multiple choice geography night sky types of galaxies galaxies constellations

Which of the following constellation contains the Pole Star?

  1. Ursa Major

  2. Ursa Minor

  3. Pleides

  4. Orion
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ursa Minor is located at the north celestial pole and contains the famous Little Dipper asterism, with Polaris, the North Star, located at the end of the dipper handle.

Multiple choice physics the universe types of galaxies galaxies constellations
Fill in the blank:
A vast collection of billions of stars is called a _______.

  1. universe

  2. galaxy

  3. constellation

  4. none of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Galaxy is a system of millions or billions of stars, together with gas and dust, held together by gravitational attraction.
Earth is is Milky way galaxy.
Multiple choice physics the universe types of galaxies galaxies constellations

Community or collection of stars is called:

  1. solar system

  2. galaxy

  3. planet

  4. milky way
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The solar system is the planetary system, where we live. It consists of the Sun and its planets, including the Earth.

A galaxy is a collection of millions of stars which are bound together to form a specific shape.
Planet is a body which revolves around a star. For eg:- The earth is a planet of the Sun which is a star.
Milky Way is the name of our galaxy. The sun and the earth are in the Milky Way.

Multiple choice physics the universe types of galaxies galaxies constellations

Milky Way is moving in local group of galaxies with a speed of:

  1. $300 \ light\ years \ {s}^{-1}$
  2. $300\ light\ years\ {hr}^{-1}$
  3. $300\ km$ ${s}^{-1}$
  4. $300m$ ${s}^{-1}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
$Milky \ Way$ moves through space within the cluster of galaxies it is a member of. This cluster, in turn, moves through space towards yet another larger cluster of galaxies off in the direction of the constellation $Virgo$. This speed is approximately $300 km/s.$
Multiple choice physics the universe types of galaxies galaxies constellations

The total mass of all stars in Milky Way galaxy is about:

  1. $2\times {10}^{41}\ kg$
  2. $2\times {10}^{31}\ kg$
  3. $2\times {10}^{21}\ kg$
  4. $2\times {10}^{11}\ kg$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Total mass of stars in the Milky Way galaxy is about $1.9 \times 10^{41}\ kg$ 
or $=2 \times 10^{41}\ kg$.
Multiple choice physics the universe types of galaxies galaxies constellations

Fill in the blank:

If $V$ is the velocity of a receding galaxy and $R$ is the distance of the galaxy from the Earth. Then the relation between $V$ and $R$ is _______ .

  1. $V \propto \displaystyle\frac{1}{R}$
  2. $V \propto {R}^{2}$
  3. $V \propto R$
  4. $V \propto \displaystyle\frac{1}{{R}^{2}}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

As per Hubble Expansion Law, $H=\displaystyle \frac{V}{R}$,

where $H$ is Hubble constant. 
So, $V \propto R$.

Multiple choice physics the universe types of galaxies galaxies constellations

The distance between the galaxy Andromeda and Earth is ________ light years.

  1. $2 \times {10}^{6}$
  2. $3 \times {10}^{8}$
  3. $22 \times {10}^{16}$
  4. $12 \times {10}^{8}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Distance between galaxy Andromeda and Earth is $2\times { 10 }^{ 6 }$

Ans : $2\times { 10 }^{ 6 }$
 

Multiple choice physics the universe types of galaxies galaxies constellations

Galaxies are categorized on basis of their shape which includes:

  1. spiral shape galaxies

  2. elliptical galaxies

  3. irregular galaxies

  4. all of above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Galaxies are innumerous in the earth and are described by various shape which include irregular shape, spiral shape, eliptical shape and barred. 

Answer is $D$

Multiple choice physics the universe types of galaxies galaxies constellations

Besides our own galaxy there are about ______ other galaxies scattered all over the universe.

  1. 2 billion

  2. 100 billion

  3. 10000 billion

  4. 1000000 billion
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Besides our own galaxy, there are about 100 billion other galaxies scattered all over the universe.
Its a fact.
Multiple choice physics the universe types of galaxies galaxies constellations

State whether true or false:

Milky Way is a family of stars, with dust and hydrogen, to which our Sun belongs.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A galaxy is vast collection of stars, dust and hydrogen gas. The solar system, our own Sun and its family or its family of planets belongs to a particular galaxy known as the Milky Way. In this way, our Sun and its family members constitute a small fraction of the galaxy.
Hence, the statement is true.