If the nuclear fusion reaction of converting 4 H ! He occurs at an(adsbygoogle = window.adsbygoogle || []).push({});

efficiency of 0.7%, and that mass is converted into energy according

to the equation E = mc2, then estimate the Main Sequence lifetime

of the Sun (spectral type G2) in years if the luminosity of the Sun is

3.83×1033 ergs s−1. Assume the Sun’s core (10% of the total mass) is

converted from H into He. The Sun’s mass is M⊙ = 1.9891 × 1033 g.

t=1/M^2.5

t=1/(91.9891x10^32)^2.5

t= the wrong answer.

What are we doing wrong?

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# Help with Life expectancy of Main Sequence stars.

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