Chapter 33, Problem 10RQ

To determine

The process that changes protostar to a full-fledged star.

Answer to Problem 10RQ

The thermonuclear explosion causes a star to born from a protostar.

Explanation of Solution

The nebula contracts gravitationally, and it spins more rapidly, flattens and hats up at its centre. Then, a protostar is born from the hot central bulge. The thermonuclear explosion causes a star to born from a protostar.

In a thermonuclear explosion, the temperature exceeds 100 million. This temperature is needed for hydrogen fusion to take place effectively.

The time from a protostar to star is not same for all the stars but depends on the mass of the star. The more massive a star, the more rapid the process will be. Collapsing into a star-like Sun takes 50 million years. The collapsing of a protostar which has high mass might take only a million years whereas, smaller stars can take more than a hundred million years.

Conclusion:

Therefore, the thermonuclear explosion causes a star to born from a protostar.