Which stars are fusing hydrogen to helium in their cores?
Group of answer choices
III (the Sun)
I, II, III, IV, and V
II and IV
I, III, and V
I, II, and IV
Main sequence stars fuse hydrogen atoms to form helium atoms in their cores. About 90 percent of the stars in the universe, including the sun, are main sequence stars. These stars can range from about a tenth of the mass of the sun to up to 200 times as massive.
Stars start their lives as clouds of dust and gas. Gravity draws these clouds together. A small protostar forms, powered by the collapsing material. Protostars often form in densely packed clouds of gas and can be challenging to detect.
Smaller bodies — with less than 0.08 the sun's mass — cannot reach the stage of nuclear fusion at their core. Instead, they become brown dwarfs, stars that never ignite. But if the body has sufficient mass, the collapsing gas and dust burns hotter, eventually reaching temperatures sufficient to fuse hydrogen into helium. The star turns on and becomes a main sequence star, powered by hydrogen fusion. Fusion produces an outward pressure that balances with the inward pressure caused by gravity, stabilizing the star.
How long a main sequence star lives depends on how massive it is. A higher-mass star may have more material, but it burns through it faster due to higher core temperatures caused by greater gravitational forces. While the sun will spend about 10 billion years on the main sequence, a star 10 times as massive will stick around for only 20 million years. A red dwarf, which is half as massive as the sun, can last 80 to 100 billion years, which is far longer than the universe's age of 13.8 billion years. (This long lifetime is one reason red dwarfs are considered to be good sources for planets hosting life, because they are stable for such a long time.)
Which stars are fusing hydrogen to helium in their cores? Group of answer choices III (the...
In one fusion reaction that occurs in the cores of certain stars, a nucleus of helium-4 (4He, with two protons and two neutrons) fuses with a nucleus of neon-20 (20Ne, with 10 protons and 10 neutron) to form a nucleus of magnesium-24 (24Mg, with 12 protons and 12 neutrons). A gamma-ray photon (γ) is also produced: 4He + 20Ne → 24Mg + γ (a) Rank the following nuclei in order of their binding energy per nucleon, from largest to smallest....
choose correct answer. no explanation needed QUESTION 21 luminosity b о в А км The figure above shows groups of stars on the H-R diagram, delineated broadly by groups (a) through (e). Which group represents stars that are hot and dim? a b OOooo QUESTION 22 luminosity b ов А F G KM The figure above shows groups of stars on the H-R diagram, delineated broadly by groups (a) through (e). Which group represents stars of the smallest radi? a...
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please answer will rate Which is the most acidic hydrogen in the following compound? V o H HAI CN H HII IV H Hн A. III B. I C. II D.V E. IV
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