The Life of a Star
3 marks · EasyName the stage of a star's life just before it becomes a main sequence star.
State what process starts at the beginning of the main sequence stage.
How long does the main sequence stage typically last for a star like the Sun?
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(a) Stellar nebula (or nebula)
(b) Nuclear fusion (of hydrogen nuclei)
(c) Millions (or billions) of years
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Marking points
B1 (a) · 1 mark · Correctly names 'nebula' or 'stellar nebula'.
B1 (b) · 1 mark · States nuclear fusion (accept hydrogen fusion).
B1 (c) · 1 mark · States millions or billions of years.
Worked solution
a) The stage just before the main sequence is called a stellar nebula (or simply nebula).
b) The process that starts is nuclear fusion of hydrogen nuclei.
c) The main sequence can last for millions or even billions of years for stars like the Sun.