ASTR 1P01/02: Introduction to Astronomy I/II

Practice Exam

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

Which of the following has the strongest magnetic field?

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

Question 2

A white dwarf...

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

Question 3

In the process of star formation, after a core starts contracting but before hydrogen fusion begins, we have...

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

Question 4

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

H II regions.
Hot gas.
Molecular clouds.

Question 5

Which force tries to expand every star throughout its life?

Pressure.
Electromagnetism.
Gravity.

Question 6

At the end of the life of a star with 20 solar masses, just before gravitational collapse, where would you expect to find iron?

In the outermost layer.
In the core.
In a middle layer.

Question 7

The triple-alpha process starts by fusing together two...

Carbon nuclei.
Helium nuclei.
Beryllium nuclei.

Question 8

The carbon atoms in your body were most likely created in...

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

Question 9

If a star has more mass...

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

Question 10

Consider a star with an initial mass of 15 solar masses. What will be this star's final state?

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

Question 11

A radiation-powered pulsar is currently 3 million years old. When it will be 6 million years old, it will rotate...

Slower.
At the same speed.
Faster.

Question 12

Which is the least dense?

Earth's atmosphere
Interstellar dust
Interstellar gas

Question 13

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

Iron.
Hydrogen.
Helium.

Question 14

He I stands for...

Ionized hydrogen.
Ionized helium.
Neutral helium.

Question 15

How long will a star with approximately 3.3 solar masses stay on the main sequence?

Approximately 10 million years.
Approximately 500 million years.
Approximately 14 billion years.

Question 16

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

Red giant.
Main sequence.
White dwarf.

Question 17

What is a nova?

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

Question 18

A reflection nebula...

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

Question 19

What is interstellar extinction?

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

Question 20

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

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

Question 21

Which is bigger?

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

Question 22

Which kind of region is the least common?

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

Question 23

What are the least common particles in cosmic rays?

Electrons or positrons.
Helium nuclei.
Protons.

Question 24

Compared to neutron stars, white dwarfs are...

More dense.
Less dense.
Just as dense.

Question 25

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.