After converting all its hydrogen to helium, a particular star is 100% helium in composition. It now proceeds to convert the helium to carbon via the triple alpha process

. The mass of the star is , and it generates energy at the rate of . We have to calculate the time in which all helium will be converted into carbon.

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Helium is converted by fusion in a star to carbon via the triple alpha process

. The mass of the star is . It generates energy at the rate of .

The mass of a atom is 4.002603 u. The total number of atoms in the star will be

Three nuclides undergo fusion to form a atom by releasing 7.27 MeV energy. Therefore, the total energy that will be released by conversion of all helium of the star will be

The star is generating energy at the rate of . Therefore, the time in which all its helium will be converted into helium will be