Questions: Where does hydrogen fusion take place in a red giant star? A shell around the core There is no hydrogen fusion in a red giant star Throughout the entire structure evenly On the surface Inside the core Question 5 2 pts When a white dwarf star accretes material from a binary companion, re-ignites nuclear fusion, and explodes, what phenomenon do we observe? Nova HII Region Brown Dwarf Black Hole Nucleosynthesis

Solution Steps

In a red giant star, hydrogen fusion does not occur in the core. Instead, it takes place in a shell surrounding the core. This is because the core has exhausted its hydrogen fuel and is primarily composed of helium. The hydrogen in the outer layers continues to fuse in a shell around the core.

Given the options:

• A shell around the core
• There is no hydrogen fusion in a red giant star
• Throughout the entire structure evenly
• On the surface
• Inside the core

The correct answer is that hydrogen fusion occurs in a shell around the core.

When a white dwarf star accretes material from a binary companion, it can reach a critical mass that reignites nuclear fusion. This can lead to a thermonuclear explosion, which is observed as a nova.

Given the options:

• Nova
• HII Region
• Brown Dwarf
• Black Hole
• Nucleosynthesis

The correct answer is a nova, which is the explosion observed when a white dwarf reignites nuclear fusion after accreting material.

Final Answer