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

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 2

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

7
6
8

Question 3

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

0.
+1.
-1.

Question 4

A neutron is made of...

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

Question 5

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 6

Which of the following is a blue giant?

M2 III
M5 V
O4 III

Question 7

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.

Question 8

I see a very faint star. This could mean:

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

Question 9

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 10

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 11

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.
9 times more energy.
3 times less energy.

Question 12

Which of the following stars is the brightest 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 13

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

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

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

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 kinetic energy of the produced photons.
Its rest energy is converted into gravitational potential energy of the produced photons.

Question 16

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

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

Question 17

Which of the following stars is the hottest?

K9
K3
K5

Question 18

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

6 parsecs.
5 parsecs.
4 parsecs.

Question 19

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

Blue.
Green.
Red.

Question 20

Which of the following is the shortest?

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

Question 21

What is nuclear fusion?

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

Question 22

Which of the following is a main-sequence star?

B5 II
G2 IV
K6 V

Question 23

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 24

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?

RR Lyrae variables
Cepheid variables
Stellar parallax

Question 25

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.
4.
1.