Chapter 12, Problem 1RD

To determine

The amount of time a star like Sun keeps burning hydrogen in its core.

Answer to Problem 1RD

The fusion of hydrogen into helium keeps the star burning at is its core. It will last for about 10 billion years and after the depletion of the hydrogen at the sun’s core, the fusion occurs in the shell around the sun’s core for about another billion years.

Explanation of Solution

The sun produces heat and light energy by fusing hydrogen into helium at its core. As sun belongs to main sequence star, stars like sun too fuse hydrogen in to helium at its core for about 10 billion years. The fusion occurs as the huge mass above the Sun’s core falls on it thereby fusing hydrogen to helium. This fusion reaction releases enormous amount of energy and counters this mass crunch.

The mass crunch and the fusion reaction continue at the core till the hydrogen is depleted in the core. Then the fusion of hydrogen continues for another billion years around the core.

Conclusion:

Thus, the fusion of hydrogen in to helium keeps the star burning at is its core. It will last for about 10 billion years and after the depletion of the hydrogen at the sun’s core, the fusion occurs in the shell around the sun’s core for about another billion years.