The Chandrasekhar limit is the maximum mass of which stellar remnant?
- A.A white dwarf
- B.A neutron star
- C.A black hole
- D.A red giant
Correct answer
Explanation
The correct answer is A, a white dwarf. Subrahmanyan Chandrasekhar showed that a white dwarf, which is supported against gravity by the pressure of degenerate electrons, cannot have a mass greater than about 1.4 times the mass of the Sun; beyond that limit the star collapses further, and the work brought him the Nobel Prize in Physics in 1983. Option B, a neutron star, is what remains after such a collapse and a supernova explosion, and its own upper limit of mass is a different and less exactly known figure. Option C, a black hole, is formed when even neutron pressure cannot hold the matter up, and it has no upper limit of this kind. Option D, a red giant, is not a remnant at all but a stage in the life of a star, reached when the hydrogen of its core is exhausted and its outer layers expand and cool.
Read the full article: Space Science: Stars, Galaxies and Satellites Notes
Practice Questions
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- A.Fusion of heavy nuclei
- B.Fusion of lighter nuclei
- C.Fission of light nuclei
- D.Fission of heavy nuclei
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Read the full explanation →What is the reason behind the twinkling of stars?
- A.Scattering of light by dust particles
- B.Internal reflection of light by clouds
- C.Atmospheric refraction of star light
- D.Dispersion of light by water droplets
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A star is so far away that it is a point source of light.
Read the full explanation →Once a satellite has been launched into orbit, the only force governing its motion is the force of ______.
- A.gravity
- B.elasticity
- C.friction
- D.fuel driven
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A satellite is given the required height and speed by its launch vehicle, and after that no engine is needed: the gravitational pull of the earth alone acts on it and provides the centripetal force that keeps it in a curved path, so the satellite keeps falling towards the earth…
Read the full explanation →A light year is a unit of
- A.Time
- B.Distance
- C.Brightness
- D.Mass
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A light year is the distance travelled by light in vacuum in one year, which is about 9.46 times ten to the power twelve kilometres, or roughly nine and a half trillion kilometres.
Read the full explanation →Which is the nearest star to the earth after the Sun?
- A.Sirius
- B.Proxima Centauri
- C.Polaris
- D.Betelgeuse
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