Top Posters
Since Sunday
L
4
d
4
3
k
3
k
3
j
3
k
3
b
3
f
3
b
3
d
3
h
3
Home Q & A Board Science-Related Homework Help Physics
New Topic  
tqwolfork tqwolfork
wrote...
Go to Answer
Posts: 23
Rep: 0 0
10 years ago
What is the source of energy in a collapsing protostar? At what point does that protostar become a main sequence star? What events signals the end of the main sequence life of a star?
Read 419 times
2 Replies
Replies
wrote...
#1
10 years ago
Whole books are dedicated to these questions but in a nutshell:

Gravity causes the star to collapse.  Gas pressure causes heat and the pressure and temperature increase (for a suitably sized star) until such time as Hydrogen Fusion begins.  Once the star has reached equilibrium it enters the main sequence.

Once the hydrogen fuel source in the core depletes the star leaves the main sequence and stars climbing the giant branch on the HR diagram for the first time.
Answer accepted by topic starter
dbassandbassan
wrote...
#2
Posts: 23
Rep: 0 0
10 years ago
Sign in or Sign up in seconds to unlock everything for free
This verified answer contains over 110 words.
1

Related Topics
New Topic      
Quick Reply
Explore
Post your homework questions and get free online help from our incredible volunteers
  886 People Browsing
 118 Signed Up Today
Start New Topic Take the Tour CoursesNew Study Tools Topics Trending Browse by Textbook
Live Chat
Related Images
  
 337
  
 2601
  
 206
Your Opinion
What percentage of nature vs. nurture dictates human intelligence?
Votes: 436
Previous poll results: What's your favorite funny biology word?