01
True or false
1 point
In a stable star, inward gravitational pull is balanced by outward pressure from the hot interior.
Free Practice Quiz Question List
05 How Stars Work Online Quiz Questions
Use this free practice quiz with 20 questions to review 05 How Stars Work, test your knowledge, and prepare for your next test or exam.
20 questions
02
Choose one
1 point
Which region of the Sun is the visible layer from which most sunlight escapes?
- A
The core
- B
The photosphere
- C
The radiative zone
- D
The convective zone
03
Fill in the blank
1 point
In the Sun’s radiative zone, energy moves outward mainly as .
04
Written response
1 point
In the simplified net description of the Sun’s fusion process, how many hydrogen nuclei ultimately combine to form one helium-4 nucleus?
05
Choose one
1 point
Which description best explains how energy is transported through the Sun’s convective zone?
- A
Energy travels mainly through neutrinos moving outward.
- B
Energy travels mainly by photons being absorbed and re-emitted.
- C
Large currents of plasma carry energy outward.
- D
Energy is carried by solid material rising and sinking.
06
Choose all
1 point
Select all statements that correctly describe the Sun’s interior.
- A
The Sun is made of plasma throughout its interior.
- B
The Sun has a solid interior beneath its photosphere.
- C
The core is the Sun’s hottest, densest region.
- D
The photosphere is a solid surface.
07
True or false
1 point
Many neutrinos produced in the Sun travel outward almost directly because they interact very weakly with matter.
- A
True
- B
False
08
Fill in the blank
1 point
In the Sun’s convective zone, hotter material ; after releasing energy, cooler material .
09
Written response
1 point
What is the name of the dominant fusion process in the Sun?
10
Choose one
1 point
If pressure in a star falls and gravity begins to compress it, which response can help restore balance?
- A
Gravity weakens, cooling the core and stopping all fusion.
- B
Gravity compresses the star, heating its core and potentially increasing fusion.
- C
Outward pressure increases immediately, expanding the star without changing its core.
- D
The star’s material becomes solid, preventing further compression.
11
Choose all
1 point
Which statements about the Sun’s simplified net fusion process are correct? Select all that apply.
- A
The net process forms a helium-4 nucleus.
- B
Energy is released.
- C
The helium-4 nucleus has slightly more mass than the original particles.
- D
Neutrinos and positrons are produced along the way.
12
Choose one
1 point
What does it mean that the Sun is a main-sequence star?
- A
Hydrogen fusion in its core supplies its energy during a long-lived phase.
- B
It has stopped fusing hydrogen and is cooling as a remnant.
- C
It produces energy only through ordinary chemical burning.
- D
It is at the brief stage of forming from a collapsing cloud.
13
Choose one
1 point
A model of the Sun’s interior must represent its material correctly. Which description fits the Sun’s interior?
- A
A solid with a thin layer of gas around it
- B
Plasma throughout
- C
Liquid beneath a solid outer shell
- D
Gas surrounding a liquid core
14
Choose one
1 point
In a model of the Sun’s convective zone, which motion of plasma helps transport energy outward?
- A
Photons carry energy outward by traveling directly through empty space
- B
Cooler material rises while hotter material sinks
- C
Hotter material rises and cooler material sinks
- D
Hydrogen nuclei move outward and fuse in the photosphere
15
Choose one
1 point
Why does energy take a slow, indirect path through the Sun’s radiative zone?
- A
Photons are repeatedly absorbed and re-emitted or scattered by matter
- B
Large plasma currents carry energy through the entire zone
- C
Neutrinos are repeatedly absorbed and re-emitted by matter
- D
Fusion carries energy outward by moving the core to the surface
16
True or false
1 point
The Sun is typical as a stable, hydrogen-fusing star, but it does not represent the full range of stars’ masses, temperatures, brightnesses, and lifetimes.
- A
True
- B
False
17
Written response
1 point
What is the name of the dominant process by which hydrogen nuclei fuse in the Sun?
18
Choose one
1 point
Which region is the visible layer from which most sunlight escapes?
- A
Core
- B
Radiative zone
- C
Convective zone
- D
Photosphere
19
Written response
1 point
Positively charged protons repel one another, making fusion rare. What kind of effects allow a small fraction of them to get close enough to fuse?
20
Open ended
1 point
A star produces energy in its interior over a long period. What does it mean for the star to maintain an energy balance? Explain what happens to the energy produced inside.