A(n) ____ is well supported (observationally and/or experimentally) system of rules and principles that can be applied to a wide variety of circumstances but that is not universally accepted.
a. hypothesis
b. paradigm
c. theory
d. model
Question 2The lower edge of the Main Sequence band is known as ____ and represents the location in the HR-diagram at which stars begin their lives as main sequence stars.
a. the Coulomb barrier
b. hydrostatic equilibrium
c. the birth line
d. the zero-age main sequence
e. the evolutionary track
Question 3A(n) ____________ is a description of some natural phenomenon that can't be right or wrong. It is merely a convenient way to think about a natural phenomenon.
a. hypothesis
b. paradigm
c. natural law
d. model
e. theory
Question 4The average star spends ____ of its lifetime on the main sequence.
a. 1
b. 2
c. 10
d. 20
e. 90
Question 5A(n) ____ is a single conjecture that can be tested.
a. hypothesis
b. paradigm
c. natural law
d. model
e. theory
Question 6____ are star-like objects that contain less than 0.08 solar masses an will never raise their core temperatures high enough that the proton-proton chain can begin. Other minor fusion reactions do occur in these objects. They fall in a gap between the low-mass M dwarf stars and the massive planets in which nuclear fusion never occurs.
a. Brown dwarfs
b. Herbig-Haro objects
c. Bok globules
d. T-Tauri star
e. Main sequence stars