a. How do stars form?
b. Why do stars evolve?
What are the three end stages of stars?
lay
Why was the name black hole given?
Which types of stars end their life as a
neutron star?
Answers
Answer:
a A star is born when atoms of light elements are squeezed under enough pressure for their nuclei to undergo fusion. All stars are the result of a balance of forces: the force of gravity compresses atoms in interstellar gas until the fusion reactions begin.
b Nuclear fusion powers a star for most of its existence. Initially the energy is generated by the fusion of hydrogen atoms at the core of the main-sequence star. ... This process causes the star to gradually grow in size, passing through the subgiant stage until it reaches the red giant phase.
A planetary nebula is the final stage of a Sun-like star. As such, planetary nebulas allow us a glimpse into the future of our own solar system. A star like our Sun will, at the end of its life, transform into a red giant. Stars are sustained by the nuclear fusion that occurs in their core, which creates energy.
In neutron stars, the force of gravity has overwhelmed the resistance of electrons to compression and has forced them to combine with protons to form neutrons. ... The star ultimately becomes a black hole, a region in space so massive that no light or matter can ever escape from it.
Answer:
a.A star is born when atoms of light elements are squeezed under enough pressure for their nuclei to undergo fusion. All stars are the result of a balance of forces: the force of gravity compresses atoms in interstellar gas until the fusion reactions begin.
b.Because when you dump energy into a normal gas (in this case the star's envelope), the pressure that gas exerts increases. ... And so generally speaking, stars evolve from the main sequence over toward the upper right quadrant of the H-R diagram, eventually becoming giant or supergiant stars.
c.Red Giant Star - The biggest stars go on swelling into supergiants. Pressure at the centre becomes so immense that carbon & silicon fuse to make iron. Supergiant- Once iron forms in its centre, the star fails to give off energy, & suddenly & catastrophically collapses.
d.It is named after the physicist Stephen Hawking, who provided a theoretical argument for its existence in 1974. Hawking radiation reduces the mass and the energy of the black hole and is therefore also known as black hole evaporation.
e.Supernovae occur at the end of a massive star's life, when it is a red supergiant, with its nuclear fuel almost spent. When the central core becomes so dense that electrons and protons begin to form neutrons, it collapses catastrophically to form a neutron star.