Tag: physics

Quizzes (598) Questions (13441)

Questions Related to physics

Multiple choice physics the universe types of galaxies galaxies constellations

Cosmic or galactic year is :

  1. year in which a comet arrives.

  2. period taken by Earth to revolve around the Sun.

  3. year in which total solar eclipse occurs.

  4. period of Sun's revolution around galactic centre.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The galactic year, also known as a cosmic year, is the duration of time required for the solar system to orbit once around the center of the Milky Way galaxy. The length of one orbit range from 225 to 250 million terrestrial years.
The solar system is traveling at an average speed of 828,000 km/h or 514,000 mph within its trajectory around the galactic center, which is about one 1300th of the speed of light speed at which an object could circumnavigate the Earth's equator in 2 minutes and 54 seconds.

Multiple choice physics the universe types of galaxies galaxies constellations

Solar system revolves around the Milky Way galaxy with the speed of:

  1. $2.5$ $\text{light years} / s$

  2. $250\ km/s$ 

  3. $250\ \text{light years} / s$

  4. $2.5\ km/s$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The Solar System is travelling at an average speed of $250\ km/s$ on its trajectory around the galactic center.
The Earth belongs to Milky Way galaxy.
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

The time taken by the Sun to revolve around the centre of our galaxy is:

  1. 25 million years

  2. 100 million years

  3. 250 million years

  4. 500 million years
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The galactic year, also known as a cosmic year, is the duration of time required for the solar system to orbit once around the center of the Milky Way galaxy. 
1 galactic year is almost equal to 250 million years.
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 : $2\times { 10 }^{ 6 }$