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

Which of the following stars is the least bright in the sky?

A star with apparent magnitude +7.0.
A star with apparent magnitude -4.4.
A star with apparent magnitude +3.1.

Question 2

I see a very faint star. This could mean:

Either the distance to the star is small or the luminosity of the star is large.
Either the distance to the star is large or the luminosity of the star is small.
Either the distance to the star is large or the luminosity of the star is large.

Question 3

In an atom, the protons are located...

Inside the nucleus.
Either inside or outside the nucleus, depending on the type of atom.
Outside the nucleus.

Question 4

Object A has mass 1 kg. Object B has mass 3 kg. According to E=mc², how much rest energy does object B have compared to A?

3 times more energy.
3 times less energy.
9 times more energy.

Question 5

A star was measured to have a parallax of 0.25 arc seconds. How far away is the star?

5 parsecs.
6 parsecs.
4 parsecs.

Question 6

Photon A has wavelength 2 cm. Photon B has wavelength 1 cm. Which photon has a higher frequency?

Both have the same frequency.
Photon A.
Photon B.

Question 7

Which of the following is a blue giant?

M2 III
O4 III
M5 V

Question 8

What happens in electron-positron annihilation?

An electron and a positron annihilate each other and produce 2 photons.
An electron and a positron annihilate each other and produce 1 photon.
An electron and a positron annihilate each other and no photons are produced.

Question 9

A photon has a wavelength of 530 nm. What color is it?

Red.
Green.
Blue.

Question 10

I want to measure the distance to a star that is estimated to be a few million light-years away. Which method should I use?

Cepheid variables
RR Lyrae variables
Stellar parallax

Question 11

Which of the following is a main-sequence star?

K6 V
G2 IV
B5 II

Question 12

Compared to RR Lyrae variables, cepheid variables typically have...

Higher luminosity and longer period.
Lower luminosity and shorter period.
Higher luminosity and shorter period.

Question 13

A star is located on the top left of the H-R diagram. This star has...

Low luminosity and low temperature.
High luminosity and high temperature.
High luminosity and low temperature.

Question 14

If the spectral lines of a star shift toward blue, this means...

The star is moving away from us.
The star is not moving with respect to us.
The star is moving toward us.

Question 15

In the proton-proton chain, how many total helium nuclei do we end up with?

4.
1.
2.

Question 16

I observed an object, larger than Earth but smaller than the Sun, which generates light by deuterium fusion but not hydrogen fusion. What is it?

A star.
A brown dwarf.
A planet.

Question 17

A neutron is made of...

2 up quarks and 1 down quark.
1 up quark and 1 down quark.
1 up quark and 2 down quarks.

Question 18

Which of the following is the shortest?

1 parsec.
1 trillion kilometers.
1 light-year.

Question 19

In the H-R diagram, red dwarfs can be found...

At higher luminosity and lower temperature than the main sequence.
At higher luminosity and higher temperature than the main sequence.
On the main sequence.

Question 20

I found a helium-9 isotope. How many neutrons does it have?

7
6
8

Question 21

Which of the following stars is the coolest?

K3
K9
K5

Question 22

If a particle has charge +1, what would be the charge of its antiparticle?

+1.
0.
-1.

Question 23

Star A has brighter apparent magnitude than star B. What does that say about the luminosity of the two stars?

There's no way to know unless we also know the distance to each star.
Star A is more luminous.
Star B is more luminous.

Question 24

What kind of mass is defined as resistance of an object to acceleration?

Neither of the other options is correct.
Inertial mass.
Gravitational mass.

Question 25

Which is the dominant process used in a star with 2.7 solar masses to generate light?

Deuterium fusion.
The proton-proton chain.
The CNO cycle.