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

A neutron 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 2

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 3

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

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

Question 4

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

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

Question 5

Which of the following is the longest?

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

Question 6

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

4.
2.
1.

Question 7

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

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

Question 8

What happens in electron-positron annihilation?

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.
An electron and a positron annihilate each other and produce 2 photons.

Question 9

Which of the following stars is the hottest?

K9
K5
K3

Question 10

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

Red.
Green.
Blue.

Question 11

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

0.
-1.
+1.

Question 12

In an atom, the protons are located...

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

Question 13

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

5 parsecs.
4 parsecs.
6 parsecs.

Question 14

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

Question 15

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 16

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.
9 times more energy.
3 times more energy.

Question 17

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 18

Which of the following is a red dwarf?

M5 V
G2 V
O4 III

Question 19

Which of the following stars is the brightest in the sky?

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

Question 20

If the spectral lines of a star shift toward blue, 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 21

Star A has brighter absolute 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 22

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

6
8
7

Question 23

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 24

What is nuclear fusion?

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

Question 25

Which of the following is a main-sequence star?

B5 II
G2 IV
K6 V