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 +3.1.
A star with apparent magnitude -4.4.

Question 2

In an atom, the electrons are located...

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

Question 3

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
Stellar parallax
RR Lyrae variables

Question 4

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 5

A proton is made of...

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

Question 6

Which of the following is a bright giant?

B5 II
K6 V
G2 IV

Question 7

What is nuclear fusion?

The process where nuclei are destroyed and converted into pure energy.
The process where light nuclei combine into heavier nuclei.
The process where heavy nuclei split into lighter nuclei.

Question 8

A star is located on the bottom right of the H-R diagram. This star has...

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

Question 9

Which of the following stars is the hottest?

K5
K3
K9

Question 10

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

8
7
6

Question 11

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

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

Question 12

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

Question 13

A star was measured to have a parallax of 0.2 arc seconds. How far away is the star?

5 parsecs.
6 parsecs.
4 parsecs.

Question 14

In the H-R diagram, red giants 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 15

I see a very faint star. This could mean:

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

Question 16

Object A has mass 1 kg. Object B has mass 9 kg. According to E=mc², how much rest energy does object B have compared to A?

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

Question 17

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

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

Question 18

What kind of mass is defined as the strength of an object's gravitational field?

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

Question 19

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

Green.
Red.
Blue.

Question 20

In the proton-proton chain, how many total hydrogen nuclei do we start with? (Remember that steps 1 and 2 happen twice in a full chain!)

1.
4.
2.

Question 21

Which of the following is the shortest?

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

Question 22

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

-1.
0.
+1.

Question 23

Which of the following is a blue giant?

M5 V
M2 III
O4 III

Question 24

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 planet.
A star.
A brown dwarf.

Question 25

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

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