Final Exam Flashcards
If our sun were to be replaced with a black hole of identical mass, what would happen to the earth?
Nothing would happen to the orbit of the earth.
Which takes longer to form, stars the mass of the sun or stars ten times the mass of the sun?
Mass of the sun.
Of the following, which is the most important factor that causes fusion in the cores of stars to be highly dependent on the temperature of the core?
Because of the difficulties in getting fusion reaction to occur.
What is the difference between the diameter of our galaxy and the diameter of our sun? (Hint: how many stars are in our galaxy?)
About a factor of a trillion.
When is a star considered born?
When fusion starts in the core of the star.
What is the expected lifetime of a 10 solar mass star?
100 million years.
What happens most of the time when two protons move directly toward each other in the core of a star?
They are repelled.
How does the core of the sun keep itself from collapsing during its current part of its lifetime?
Gas and radiation pressure.
How does a neutron star keep itself from collapsing?
Neutron degeneracy pressure.
What type of spectrum will a cold black body produce?
Continuum.
What will our sun become when it does?
A white dwarf.
90% of our galaxy’s mass is in what form?
Dark matter.
Why are black holes black?
They emit no light.
