i) Briefly explain why a star of mass 0.5A/1,, collapses to form a white dwarf when the nuclear reactions in its core cease.
(ii) That is the maximum theoretical mass of a white dwarf? Describe (in about 100 words) what happens to a star if its mass exceeds this value.
(iii) What is the maximum theoretical mass of a neutron star? What typical values are derived from observations?
(iv) Why, despite your answer to parts (ii) and (iii) above, does a main sequence star of 5M, also form a white dwarf at the end of its life?