Question 1

Which of the following is not a good reason to place observatories on remote mountain tops?

Accepted Answer

A) to be able to observe at radio wavelengths 
B) to reduce light absorption 
C) to reduce light pollution 
D) to reduce light distortion 
A) to be able to observe at radio wavelengths 
B) to reduce light absorption 
C) to reduce light pollution 
D) to reduce light distortion

Question 2

Doppler shifted hydrogen absorption lines are seen in the spectrum of a star. The hydrogen line at 656.28 nm is seen to be shifted to 656.08 nm. How large is the shift in wavelength?

Accepted Answer

A) 0)2 nm 
B) 2 nm 
C) 0)02 nm 
A) 0)2 nm 
B) 2 nm 
C) 0)02 nm

Question 3

The energies of two photons you might detect emitted by hydrogen atoms are 10.2 and 2.1 eV. Which photon has the longest wavelength?

Accepted Answer

A) the 2.1 eV photon 
B) the 10 eV photon 
C) They both have the same wavelength. 
A) the 2.1 eV photon 
B) the 10 eV photon 
C) They both have the same wavelength.

Question 4

Which of the following observational techniques is most appropriate for measuring Doppler shifts?

Accepted Answer

A) timing (measuring how the amount of light changes with time) 
B) imaging (taking a picture) 
C) spectroscopy (taking a spectrum) 
A) timing (measuring how the amount of light changes with time) 
B) imaging (taking a picture) 
C) spectroscopy (taking a spectrum)

Question 5

Which of the following properties cannot be determined from a spectrum of a star?

Accepted Answer

A) surface temperature 
B) speed perpendicular to my line of sight 
C) chemical composition 
D) speed towards me or away from me 
A) surface temperature 
B) speed perpendicular to my line of sight 
C) chemical composition 
D) speed towards me or away from me

Question 6

Which of the following is not a way light and matter interact?

Accepted Answer

A) absorption 
B) emission 
C) evaporation 
D) scattering 
E) transmission 
A) absorption 
B) emission 
C) evaporation 
D) scattering 
E) transmission

Question 7

Doppler shifted hydrogen absorption lines are seen in the spectrum of a star. The hydrogen line at 656.28 nm is seen to be shifted to 656.08 nm. Is the star moving towards or away from us, or can we not tell?

Accepted Answer

A) moving towards us 
B) moving away from us 
C) There is not enough information to determine the answer. 
A) moving towards us 
B) moving away from us 
C) There is not enough information to determine the answer.

Question 8

If you heat a gas so that collisions are continually bumping electrons to higher energy levels, when the electrons fall back to lower energy levels the gas produces

Accepted Answer

A) radio waves. 
B) thermal radiation. 
C) an emission line spectrum. 
D) X- rays. 
E) an absorption line spectrum. 
A) radio waves. 
B) thermal radiation. 
C) an emission line spectrum. 
D) X- rays. 
E) an absorption line spectrum.

Question 9

Suppose you know the frequency of a photon and the speed of light. What else can you determine about the photon?

Accepted Answer

A) the chemical composition of the object that emitted it 
B) its wavelength and energy 
C) its acceleration 
D) its temperature 
A) the chemical composition of the object that emitted it 
B) its wavelength and energy 
C) its acceleration 
D) its temperature

Question 10

A radio telescope and an optical telescope of the same size have the same angular resolution.

Accepted Answer

A) True 
 B)False

Question 11

Which of the following statements about thermal radiation is always true?

Accepted Answer

A) A hot object emits photons with a higher average energy than a cool object. 
B) A hot object emits more radio waves than a cool object. 
C) A hot object emits more X- rays than a cool object. 
D) A hot object emits photons with a longer wavelength than a cool object. 
A) A hot object emits photons with a higher average energy than a cool object. 
B) A hot object emits more radio waves than a cool object. 
C) A hot object emits more X- rays than a cool object. 
D) A hot object emits photons with a longer wavelength than a cool object.

Question 12

Emission lines from different ionization states of the same element appear in the same place in the spectrum.

Accepted Answer

A) True 
 B)False

Question 13

Suppose you want to know the chemical composition of a distant star. Which piece of information is most useful to you?

Accepted Answer

A) the Doppler shift of the star's spectrum 
B) the wavelengths of spectral lines in the star's spectrum 
C) whether the star's spectrum has more emission lines or more absorption lines 
D) the peak energy of the star's thermal radiation 
A) the Doppler shift of the star's spectrum 
B) the wavelengths of spectral lines in the star's spectrum 
C) whether the star's spectrum has more emission lines or more absorption lines 
D) the peak energy of the star's thermal radiation

Question 14

What is the angular resolution of the human eye?

Accepted Answer

A) about 1 arcminute, or 1/60 of a degree 
B) about 1 degree 
C) about 1 milliarcsecond 
D) about 1 arcsecond (1/3600 of a degree) 
A) about 1 arcminute, or 1/60 of a degree 
B) about 1 degree 
C) about 1 milliarcsecond 
D) about 1 arcsecond (1/3600 of a degree)

Question 15

An electron- volt is

Accepted Answer

A) the energy jump between the first and second energy levels of hydrogen. 
B) an amount of energy much smaller than a joule. 
C) the energy of one electron. 
D) the charge of one electron. 
E) an amount of energy much larger than a joule. 
A) the energy jump between the first and second energy levels of hydrogen. 
B) an amount of energy much smaller than a joule. 
C) the energy of one electron. 
D) the charge of one electron. 
E) an amount of energy much larger than a joule.

Question 16

X- ray telescope mirrors are very similar to optical telescope mirrors.

Accepted Answer

A) True 
 B)False

Question 17

An atom of the element iron has an atomic number of 26 and an atomic mass number of 56. If it is neutral, how many protons, neutrons, and electrons does it have?

Accepted Answer

A) 26 protons, 30 neutrons, 30 electrons 
B) 26 protons, 30 neutrons, 26 electrons 
C) 13 protons, 56 neutrons, 13 electrons 
D) 13 protons, 43 neutrons, 13 electrons 
E) 26 protons, 56 neutrons, 26 electrons 
A) 26 protons, 30 neutrons, 30 electrons 
B) 26 protons, 30 neutrons, 26 electrons 
C) 13 protons, 56 neutrons, 13 electrons 
D) 13 protons, 43 neutrons, 13 electrons 
E) 26 protons, 56 neutrons, 26 electrons

Question 18

Which of the following describes the light that can be detected from a person?

Accepted Answer

A) The person reflects many wavelengths of visible light and emits a continuum of wavelengths of infrared light. 
B) The person emits many wavelengths of visible light and reflects a continuum of wavelengths of infrared light. 
C) The person absorbs a few narrow wavelengths of visible light according to their composition. 
D) The person emits a few narrow wavelengths of visible light according to their composition. 
A) The person reflects many wavelengths of visible light and emits a continuum of wavelengths of infrared light. 
B) The person emits many wavelengths of visible light and reflects a continuum of wavelengths of infrared light. 
C) The person absorbs a few narrow wavelengths of visible light according to their composition. 
D) The person emits a few narrow wavelengths of visible light according to their composition.

Question 19

The shorter the wavelength of light, the higher its frequency.

Accepted Answer

A) True 
 B)False

Question 20

What is the purpose of adaptive optics?

Accepted Answer

A) It is a special technology that allows the Hubble Space Telescope to adapt to study many different types of astronomical objects. 
B) It allows several small telescopes to work together like a single larger telescope. 
C) It allows ground- based telescopes to observe ultraviolet light that normally does not penetrate the atmosphere. 
D) It reduces blurring caused by atmospheric turbulence for telescopes on the ground. 
A) It is a special technology that allows the Hubble Space Telescope to adapt to study many different types of astronomical objects. 
B) It allows several small telescopes to work together like a single larger telescope. 
C) It allows ground- based telescopes to observe ultraviolet light that normally does not penetrate the atmosphere. 
D) It reduces blurring caused by atmospheric turbulence for telescopes on the ground.

Which of the following is not a good reason to place observatories on remote mountain tops?

Doppler shifted hydrogen absorption lines are seen in the spectrum of a star. The hydrogen line at 656.28 nm is seen to be shifted to 656.08 nm. How large is the shift in wavelength?

The energies of two photons you might detect emitted by hydrogen atoms are 10.2 and 2.1 eV. Which photon has the longest wavelength?

Which of the following observational techniques is most appropriate for measuring Doppler shifts?

Which of the following properties cannot be determined from a spectrum of a star?

Which of the following is not a way light and matter interact?

Doppler shifted hydrogen absorption lines are seen in the spectrum of a star. The hydrogen line at 656.28 nm is seen to be shifted to 656.08 nm. Is the star moving towards or away from us, or can we not tell?

If you heat a gas so that collisions are continually bumping electrons to higher energy levels, when the electrons fall back to lower energy levels the gas produces

Suppose you know the frequency of a photon and the speed of light. What else can you determine about the photon?

A radio telescope and an optical telescope of the same size have the same angular resolution.

Which of the following statements about thermal radiation is always true?

Emission lines from different ionization states of the same element appear in the same place in the spectrum.

Suppose you want to know the chemical composition of a distant star. Which piece of information is most useful to you?

What is the angular resolution of the human eye?

An electron- volt is

X- ray telescope mirrors are very similar to optical telescope mirrors.

An atom of the element iron has an atomic number of 26 and an atomic mass number of 56. If it is neutral, how many protons, neutrons, and electrons does it have?

Which of the following describes the light that can be detected from a person?

The shorter the wavelength of light, the higher its frequency.

What is the purpose of adaptive optics?

A Modern View of the Universe

Discovering the Universe for Yourself

The Science of Astronomy

Making Sense of the Universe: Understanding Motion, Energy, and Gravity

Formation of the Solar System

Earth and the Terrestrial Worlds

Jovian Planet System

Asteroids, Comets, and Dwarf Planets: Their Nature, Orbits, and Impacts

Other Planetary Systems: the New Science of Distant Worlds

Our Star

Surveying the Stars

Star Stuff

The Bizarre Stellar Graveyard

Our Galaxy

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The Birth of the Universe

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Life in the Universe

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Exam 5: Light: the Cosmic Messenger

Which of the following is not a good reason to place observatories on remote mountain tops?

Doppler shifted hydrogen absorption lines are seen in the spectrum of a star. The hydrogen line at 656.28 nm is seen to be shifted to 656.08 nm. How large is the shift in wavelength?

The energies of two photons you might detect emitted by hydrogen atoms are 10.2 and 2.1 eV. Which photon has the longest wavelength?

Which of the following observational techniques is most appropriate for measuring Doppler shifts?

Which of the following properties cannot be determined from a spectrum of a star?

Which of the following is not a way light and matter interact?

Doppler shifted hydrogen absorption lines are seen in the spectrum of a star. The hydrogen line at 656.28 nm is seen to be shifted to 656.08 nm. Is the star moving towards or away from us, or can we not tell?

If you heat a gas so that collisions are continually bumping electrons to higher energy levels, when the electrons fall back to lower energy levels the gas produces

Suppose you know the frequency of a photon and the speed of light. What else can you determine about the photon?

A radio telescope and an optical telescope of the same size have the same angular resolution.

Which of the following statements about thermal radiation is always true?

Emission lines from different ionization states of the same element appear in the same place in the spectrum.

Suppose you want to know the chemical composition of a distant star. Which piece of information is most useful to you?

What is the angular resolution of the human eye?

An electron- volt is

X- ray telescope mirrors are very similar to optical telescope mirrors.

An atom of the element iron has an atomic number of 26 and an atomic mass number of 56. If it is neutral, how many protons, neutrons, and electrons does it have?

Which of the following describes the light that can be detected from a person?

The shorter the wavelength of light, the higher its frequency.

What is the purpose of adaptive optics?

A Modern View of the Universe

Discovering the Universe for Yourself

The Science of Astronomy

Making Sense of the Universe: Understanding Motion, Energy, and Gravity

Formation of the Solar System

Earth and the Terrestrial Worlds

Jovian Planet System

Asteroids, Comets, and Dwarf Planets: Their Nature, Orbits, and Impacts

Other Planetary Systems: the New Science of Distant Worlds

Our Star

Surveying the Stars

Star Stuff

The Bizarre Stellar Graveyard

Our Galaxy

A Universe of Galaxies

The Birth of the Universe

Dark Matter, Dark Energy, and the Fate of the Universe

Life in the Universe

Filters