Name: matt l rasmussen
Date: 1993 - 1999
I would like to know why I can not get the formula for the
mass-luminosity to give me the agreed-upon value.
Could you give a bit more information, such as what equation you are
using and the case that doesn't work?
The various sources I have looked at do not give an equation as such; they
merely state that if you graph Log(L) vs. Log(M) for a number of stars on the
main sequence, they tend to lie in a fairly thin band. But as the Encyclopedia
of Physical Science and Technology points out, during the course of a star's lif etime its luminosity
varies considerably, whereas its mass remains nearly constant; so it is clear
that no single equation will work for all stars at all stages of stellar
evolution. The above-mentioned source says that L increases approximately as M^3 for stars on the order of
10 solar masses, as M^4.5 for stars of around 1 solar mass, and as M^2 for
Further, this is only good for stars that have "just" entered the main sequence.
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