ASVAB (Armed Services Vocational Aptitude Battery)General Science (GS)Hard
Which of the following describes the process by which a star generates energy?
- AChemical combustion of hydrogen and helium.
- BGravitational collapse leading to heat generation.
- CNuclear fission of heavy elements.
- DNuclear fusion of hydrogen into helium.
Show answer & explanationAnswer & explanation
Correct answer: D. Nuclear fusion of hydrogen into helium.
Stars generate vast amounts of energy through nuclear fusion in their cores. Specifically, hydrogen nuclei fuse to form helium nuclei, releasing a tremendous amount of energy according to E=mc².
Why the other options are wrong
- A. Chemical combustion is insufficient to power a star and does not occur on that scale in stars.
- B. Gravitational collapse initiates star formation and heats the core, leading to fusion, but it is not the primary ongoing energy generation mechanism.
- C. Nuclear fission is the splitting of heavy elements, used in nuclear reactors, not the primary energy source for stars.
Stellar Energy Generation
The mechanism by which stars produce light and heat, sustaining themselves against gravitational collapse.
- Occurs in the star's core.
- Primarily nuclear fusion of hydrogen into helium.
- Releases immense amounts of energy.
Memory trick: Fusing H into He makes a star's energy glee.