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

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

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

Question 2

Which of the following is the shortest?

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

Question 3

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

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

Question 4

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

2.
1.
4.

Question 5

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

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

Question 6

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

+1.
0.
-1.

Question 7

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 8

Which of the following is a blue giant?

M2 III
O4 III
M5 V

Question 9

Which of the following stars is the hottest?

K3
K5
K9

Question 10

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 11

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

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

Question 12

I see a very bright 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 13

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 brown dwarf.
A planet.
A star.

Question 14

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

Green.
Blue.
Red.

Question 15

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

7
6
8

Question 16

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

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

Question 17

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 18

In an atom, the protons are located...

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

Question 19

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

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

Question 20

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

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

Question 21

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

Question 22

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?

Stellar parallax
Cepheid variables
RR Lyrae variables

Question 23

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 24

Which of the following is a main-sequence star?

G2 IV
K6 V
B5 II

Question 25

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

4 parsecs.
6 parsecs.
5 parsecs.