Birth of Stars

Q.

Explain the nuclear chain reaction.

Q. Explain why the Pole Star appears to be stationary in the sky and all other stars appear to revolve around it from east to west.

Q. What is the first stage of a stars life.

1. Nebula collapsing under itself
2. Supernova of old star
3. Planets collapsing
4. Fusion of atoms

Q. All stars are born in what phase of their lifecycle?

1. Supernova
2. Red giant
3. main sequence
4. stellar nebula

Q. Orion nebula glows brightly because the gas in it is energised by the stars that have already formed within it, such types of nebula are called as ___________.

1. planetary nebula
2. dark nebula
3. reflection nebula
4. emission nebula

Q.

What do you understand by the following term- Nebulae

Q. What does the forming star become when the outward pressure equals the inward force of gravity?

1. unstable secondary white dwarf
2. unstable main-sequence star
3. stable main-sequence star
4. stable secondary red giant

Q. Horse head Nebula in Orion are dense clouds of molecular hydrogen which partially or completely absorb the light from the stars behind them. These are called ___________.

1. planetary nebula
2. dark nebula
3. reflection nebula
4. emission nebula

Q. A protostar is a developing star not yet hot enough to engage in the process of:

1. nuclear fusion
2. atomic emission
3. nuclear fission
4. atomic transmission

Q. A star in the main sequence will maintain a constant size

1. as long as its helium supply holds out.
2. until it is devoured by black holes.
3. because its tendency to contract is opposed by the pressure of the hot interior.
4. provided that gravitational collapse does not overwhelm its photosphere.

Q. _________ are the outer layers of a star that are lost when the star changes from a red giant to white dwarf.

1. planetary nebula
2. dark nebula
3. emission nebula
4. reflection nebula

Q. What is the range of star masses for high-mass stars?

1. between 2 and about 10 solar masses
2. between 500 and about 1, 000 solar masses
3. between 8 and about 100 solar masses
4. between 200 and about 500 solar masses

Q. What is the name of the process that forms heavy elements from atoms like helium?

1. Nuclear Fission
2. Attraction
3. Conjugation
4. Nuclear Fusion

Q. Search and you will find.
The larger the mass of a star the faster is its _________

Q. What happens during the Main Sequence phase of a star?

1. Hydrogen atoms are fused into helium atoms
2. The star explodes and releases energy
3. Helium atoms are fused into heavy elements
4. The star is born out of dust and gas