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

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 2

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

Question 3

Which of the following is a main-sequence star?

B5 II
G2 IV
K6 V

Question 4

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 5

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

8
7
6

Question 6

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 B is more luminous.
Star A is more luminous.

Question 7

In an atom, the protons are located...

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

Question 8

I see a very bright 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 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.

Question 9

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 10

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 11

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

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

Question 12

A photon has a wavelength of 700 nm. What color is it?

Blue.
Green.
Red.

Question 13

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

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

Question 14

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

A planet.
A star.
A brown dwarf.

Question 15

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

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

Question 16

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

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

Question 17

Which of the following is the shortest?

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

Question 18

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

0.
+1.
-1.

Question 19

A proton is made of...

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

Question 20

What happens in electron-positron annihilation?

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

Question 21

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

Cepheid variables
RR Lyrae variables
Stellar parallax

Question 22

Which of the following is a red dwarf?

G2 V
M5 V
O4 III

Question 23

Which of the following stars is the coolest?

K5
K9
K3

Question 24

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 25

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

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