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astro 1-exam 3 Questions And Correct
Answers/ Latest Update / Already
Graded Questions And Correct
Answers/ Latest Update / Already
Graded
what is the sun comprised of?
Ans: 73% hydrogen 25% helium
why is the sun stable?
Ans: outward force of gas pressure; inward force of gravity
Where does the gas pressure in the sun come from?
Ans: nuclear fusion reactions in the core at temperatures of 15
million degrees
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What is the diameter of the sun compared to earth? mass?
luminosity (compared to 100W lightbulbs?
Ans: diameter-109x; mass-333,000; luminosity- 4 x 10^24
What percent of mass in the solar system comes from the sun?
Ans: 99.9%
how long has the sun been shining? how much longer will it shine?
Ans: 4.5 billion years; 5.5 billion years
what are sunspots?
Ans: slightly cooler regions on the sun's surface
what causes sunspots? how long are their cycles?
, 3 | Page
Ans: magnetic activity preventing hot material from rising to that
region. they have 11 year cycles
what comprises helium-4? What does it release? What is it called?
Ans: 4 protons combine to make helium-4 (2 protons, 2 neutrons);
produces gamma rays; it is called the proton-proton chain
What is the first step in Nuclear fusion?
Ans: two protons stick together and one changes into a neutron to
produce deuterium (1 proton and 1 neutron)
What is the second step in Nuclear fusion?
Ans: deuterium plus proton makes helium-3 (2 protons and 1
neutron bound together)
What is the third step in nuclear fusion?
astro 1-exam 3 Questions And Correct
Answers/ Latest Update / Already
Graded Questions And Correct
Answers/ Latest Update / Already
Graded
what is the sun comprised of?
Ans: 73% hydrogen 25% helium
why is the sun stable?
Ans: outward force of gas pressure; inward force of gravity
Where does the gas pressure in the sun come from?
Ans: nuclear fusion reactions in the core at temperatures of 15
million degrees
,2 | Page
What is the diameter of the sun compared to earth? mass?
luminosity (compared to 100W lightbulbs?
Ans: diameter-109x; mass-333,000; luminosity- 4 x 10^24
What percent of mass in the solar system comes from the sun?
Ans: 99.9%
how long has the sun been shining? how much longer will it shine?
Ans: 4.5 billion years; 5.5 billion years
what are sunspots?
Ans: slightly cooler regions on the sun's surface
what causes sunspots? how long are their cycles?
, 3 | Page
Ans: magnetic activity preventing hot material from rising to that
region. they have 11 year cycles
what comprises helium-4? What does it release? What is it called?
Ans: 4 protons combine to make helium-4 (2 protons, 2 neutrons);
produces gamma rays; it is called the proton-proton chain
What is the first step in Nuclear fusion?
Ans: two protons stick together and one changes into a neutron to
produce deuterium (1 proton and 1 neutron)
What is the second step in Nuclear fusion?
Ans: deuterium plus proton makes helium-3 (2 protons and 1
neutron bound together)
What is the third step in nuclear fusion?
