Practice Test

Please solve the following questions. This is not a real exam, it will not be graded, and you do not need to submit your solutions to anyone. The questions are simply intended to help you practice for the real exam.

These questions will not appear in the exam itself. Students who don't genuinely attempt to solve the questions on their own, and only memorize the solutions, will have a very hard time in the actual exam!

This sample exam is online, but the real exam will be given in person, at a time and place indicated on the course website.

THIS IS NOT THE ACTUAL EXAM!
THIS IS JUST A PRACTICE EXAM!
THE REAL EXAM IS IN PERSON!

If you need any clarifications for these questions, you can ask for them on the course Teams channel.

Question 1

Can a white dwarf have 2.2 solar masses?

No.
Yes.
Depends on its radius.

Question 2

In which stage of its life will a star with mass similar to the Sun have the largest diameter?

White dwarf.
Red giant.
Main sequence.

Question 3

What is the frequency of light emitted in a spin-flip transition?

1.4 GHz
21 GHz
5.9 GHz

Question 4

An emission nebula...

Scatters light from nearby stars.
Blocks light.
Creates its own light.

Question 5

Which force tries to expand every star throughout its life?

Electromagnetism.
Pressure.
Gravity.

Question 6

I saw a supernova in the sky. Where did it come from?

Material ejected from a planet near death.
Material ejected from a low-mass star near death.
Material ejected from a high-mass star near death.

Question 7

Most of the volume of interstellar gas is in the form of...

H II regions.
Hot gas.
Molecular clouds.

Question 8

Which kind of region is the most common?

Both regions are equally common.
H II.
H I.

Question 9

Compared to white dwarfs, neutron stars are...

More dense.
Less dense.
Just as dense.

Question 10

Approximately how long will the Sun spend in the red giant stage?

1.3 billion years.
11 billion years.
5 million years.

Question 11

When a star is leaving the main sequence, its core is made primarily of...

Helium.
Iron.
Hydrogen.

Question 12

Which of the following has the weakest magnetic field?

A magnetar.
Planet Earth.
A normal (rotation- or accretion-powered) pulsar.

Question 13

A black dwarf...

Produces faint light with stored heat energy.
Produces bright light with energy from nuclear reactions.
Does not produce light anymore.

Question 14

The end products of the triple-alpha process are...

Beryllium nuclei.
Helium nuclei.
Carbon nuclei.

Question 15

What are the most common particles in cosmic rays?

Protons.
Helium nuclei.
Electrons or positrons.

Question 16

If a star has more mass...

Its lifetime is shorter.
Its lifetime is unaffected.
Its lifetime is longer.

Question 17

Consider a star with an initial mass of 5 solar masses. What will be this star's final state?

A white dwarf.
A brown dwarf.
A neutron star.

Question 18

The atoms in a gold ring were most likely created in...

A collision with an asteroid.
The core of a star.
A supernova.

Question 19

In the process of star formation, after hydrogen fusion begins, we have...

A protostar.
A molecular cloud.
A main-sequence star.

Question 20

What prevents a neutron star from collapsing?

Electron degeneracy pressure.
Pressure due to nuclear fusion.
Neutron degeneracy pressure and repulsion from the strong nuclear force.

Question 21

What is interstellar extinction?

The process where light from stars becomes dimmer.
The process where species of aliens become extinct.
The process where stars become extinct due to losing their hydrogen supply.

Question 22

Which is smaller?

The Local Bubble.
They are both the same size.
The Local Fluff.

Question 23

What is a Type Ia supernova?

An explosion that occurs when a new star is created.
An explosion that occurs when a white dwarf accumulates matter from its binary companion and approaches the Chandrasekhar limit.
An explosion that occurs when a white dwarf accumulates matter from its binary companion but does not approach the Chandrasekhar limit.

Question 24

He II stands for...

Ionized hydrogen.
Neutral helium.
Ionized helium.

Question 25

What is left after a Type II supernova?

A white dwarf.
A neutron star or a black hole.
Nothing.