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

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

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

Question 2

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 3

Which of the following is the longest?

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

Question 4

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

6
7
8

Question 5

Which of the following is a red dwarf?

M5 V
G2 V
O4 III

Question 6

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 star.
A planet.
A brown dwarf.

Question 7

A proton is made of...

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

Question 8

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?

Stellar parallax
RR Lyrae variables
Cepheid variables

Question 9

Which of the following is a bright giant?

B5 II
K6 V
G2 IV

Question 10

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

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

Question 11

Which of the following stars is the coolest?

K5
K9
K3

Question 12

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!)

2.
1.
4.

Question 13

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

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

Question 14

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

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

Question 15

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

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

Question 16

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

6 parsecs.
4 parsecs.
5 parsecs.

Question 17

What happens to the mass in electron-positron annihilation?

The mass is conserved, and converted into the mass of the photons.
Its rest energy is converted into gravitational potential energy of the produced photons.
Its rest energy is converted into kinetic energy of the produced photons.

Question 18

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

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

Question 19

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 20

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

Green.
Blue.
Red.

Question 21

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 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 22

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

0.
+1.
-1.

Question 23

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 24

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 25

In an atom, the electrons are located...

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