Question 1

Energy and power are different words for the same thing.

Accepted Answer

A) True 
 B)False

Question 2

A gas heated to millions of degrees would emit

Accepted Answer

A) mostly radio waves. 
B) mostly X-rays. 
C) mostly ultraviolet light. 
D) an equal amount of all wavelengths of light. 
E) no light,because it is too hot. 
A) mostly radio waves. 
B) mostly X-rays. 
C) mostly ultraviolet light. 
D) an equal amount of all wavelengths of light. 
E) no light,because it is too hot.

Question 3

What does atomic number refers to?

Accepted Answer

the number

Question 4

How does the spectrum of a molecule differ from the spectrum of an atom?

Accepted Answer

A) A molecule does not have spectral lines due to electrons changing energy levels. 
B) A molecule has additional spectral lines due to changes in its rotational and vibrational energies. 
C) Molecules only have spectral lines at ultraviolet wavelengths. 
D) Most atoms only have spectral lines at infrared wavelengths. 
E) An atom has a wider range of spectral lines than molecules. 
A) A molecule does not have spectral lines due to electrons changing energy levels. 
B) A molecule has additional spectral lines due to changes in its rotational and vibrational energies. 
C) Molecules only have spectral lines at ultraviolet wavelengths. 
D) Most atoms only have spectral lines at infrared wavelengths. 
E) An atom has a wider range of spectral lines than molecules.

Question 5

What do we mean when we say that electron energy levels in atoms are quantized?

Accepted Answer

The electrons can ha

Question 6

Consider an atom of carbon in which the nucleus contains 6 protons and 7 neutrons.What is its atomic number and atomic mass number?

Accepted Answer

A) atomic number = 6;atomic mass number = 13 
B) atomic number = 6;atomic mass number = 7 
C) atomic number = 13;atomic mass number = 6 
D) atomic number = 7;atomic mass number = 13 
A) atomic number = 6;atomic mass number = 13 
B) atomic number = 6;atomic mass number = 7 
C) atomic number = 13;atomic mass number = 6 
D) atomic number = 7;atomic mass number = 13

Question 7

The energy levels of an element and its ion are the same.

Accepted Answer

A) True 
 B)False

Question 8

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

Accepted Answer

A) A hot object emits more X-rays than a cool object. 
B) A hot object emits more radio waves than a cool object. 
C) A hot object emits more total radiation than a cool object. 
D) A hot object emits more total radiation per unit surface area than a cool object. 
E) A hot object emits less total radiation than a cool object. 
A) A hot object emits more X-rays than a cool object. 
B) A hot object emits more radio waves than a cool object. 
C) A hot object emits more total radiation than a cool object. 
D) A hot object emits more total radiation per unit surface area than a cool object. 
E) A hot object emits less total radiation than a cool object.

Question 9

Suppose that Star X and Star Y both have redshifts,but Star X has a larger redshift than Star Y.What can you conclude?

Accepted Answer

A) Star X is moving away from us faster than Star Y. 
B) Star Y is moving away from us faster than Star X. 
C) Star X is hotter than Star Y. 
D) Star X is moving away from us and Star Y is moving toward us. 
A) Star X is moving away from us faster than Star Y. 
B) Star Y is moving away from us faster than Star X. 
C) Star X is hotter than Star Y. 
D) Star X is moving away from us and Star Y is moving toward us.

Question 10

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

Accepted Answer

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

Question 11

Which of the following cannot be described by a field?

Accepted Answer

A) gravitational forces 
B) electrical forces 
C) magnetic forces 
D) radiation pressure 
A) gravitational forces 
B) electrical forces 
C) magnetic forces 
D) radiation pressure

Question 12

We can learn a lot about the properties of a star by studying its spectrum.All of the following statements are true except one.Which one?

Accepted Answer

A) The peak of the star's thermal emission tells us its temperature: Hotter stars peak at shorter (bluer)wavelengths. 
B) The total amount of light in the spectrum tells us the star's radius. 
C) We can identify chemical elements present in the star by recognizing patterns of spectral lines that correspond to particular chemicals. 
D) We can look at Doppler shifts of spectral lines to determine the star's speed toward or away from us. 
A) The peak of the star's thermal emission tells us its temperature: Hotter stars peak at shorter (bluer)wavelengths. 
B) The total amount of light in the spectrum tells us the star's radius. 
C) We can identify chemical elements present in the star by recognizing patterns of spectral lines that correspond to particular chemicals. 
D) We can look at Doppler shifts of spectral lines to determine the star's speed toward or away from us.

Question 13

Suppose that two stars are identical in every way-for example,same distance,same mass,same temperature,same chemical composition,and same speed relative to Earth-except that one star rotates faster than the other.Spectroscopically,how could you tell the stars apart?

Accepted Answer

A) The faster rotating star has wider spectral lines than the slower rotating star. 
B) The faster rotating star will have an emission line spectrum while the slower rotating star will have an absorption line spectrum. 
C) The peak of thermal emission will be at a shorter wavelength for the faster rotating star than for the slower rotating star. 
D) There is no way to tell the stars apart spectroscopically,because their spectra will be identical. 
A) The faster rotating star has wider spectral lines than the slower rotating star. 
B) The faster rotating star will have an emission line spectrum while the slower rotating star will have an absorption line spectrum. 
C) The peak of thermal emission will be at a shorter wavelength for the faster rotating star than for the slower rotating star. 
D) There is no way to tell the stars apart spectroscopically,because their spectra will be identical.

Question 14

The frequency of a wave is

Accepted Answer

A) the number of peaks passing by any point each second. 
B) measured in cycles per second. 
C) measured in hertz (Hz). 
D) equal to the speed of the wave divided by the wavelength of the wave. 
E) all of the above 
A) the number of peaks passing by any point each second. 
B) measured in cycles per second. 
C) measured in hertz (Hz). 
D) equal to the speed of the wave divided by the wavelength of the wave. 
E) all of the above

Question 15

Grass is green because it absorbs green light,reflecting all other colors.

Accepted Answer

A) True 
 B)False

Question 16

When an atom absorbs a photon containing energy,any of the following can happen except which?

Accepted Answer

A) The atom becomes excited. 
B) The atom is ionized. 
C) An electron moves from an upper energy level to a lower one. 
D) An electron moves from a lower energy level to an upper one. 
A) The atom becomes excited. 
B) The atom is ionized. 
C) An electron moves from an upper energy level to a lower one. 
D) An electron moves from a lower energy level to an upper one.

Question 17

Atomic nuclei consist of protons and electrons.

Accepted Answer

A) True 
 B)False

Question 18

Suppose you have a chunk of water ice.Describe what happens to it,in terms of phases,as you raise the temperature to millions of degrees.

Accepted Answer

The ice melts into liquid,then

Question 19

The following questions refer to the diagram below.The levels represent energy levels in a hydrogen atom.Each level is labeled with its energy (above the ground state of Level 1)in units of electron/volts (eV).The labeled transitions represent an electron moving between energy levels.
  
-Which transition,as shown,is not possible?

Accepted Answer

The answer of The following questions refer to the diagram...

Question 20

The greater the wavelength of light,the greater its energy.

Accepted Answer

A) True 
 B)False

Exam 5: Light and Matter: Reading Messages from the Cosmos

Energy and power are different words for the same thing.

A gas heated to millions of degrees would emit

What does atomic number refers to?

How does the spectrum of a molecule differ from the spectrum of an atom?

What do we mean when we say that electron energy levels in atoms are quantized?

Consider an atom of carbon in which the nucleus contains 6 protons and 7 neutrons.What is its atomic number and atomic mass number?

The energy levels of an element and its ion are the same.

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

Suppose that Star X and Star Y both have redshifts,but Star X has a larger redshift than Star Y.What can you conclude?

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

Which of the following cannot be described by a field?

We can learn a lot about the properties of a star by studying its spectrum.All of the following statements are true except one.Which one?

Suppose that two stars are identical in every way-for example,same distance,same mass,same temperature,same chemical composition,and same speed relative to Earth-except that one star rotates faster than the other.Spectroscopically,how could you tell the stars apart?

The frequency of a wave is

Grass is green because it absorbs green light,reflecting all other colors.

When an atom absorbs a photon containing energy,any of the following can happen except which?

Atomic nuclei consist of protons and electrons.

Suppose you have a chunk of water ice.Describe what happens to it,in terms of phases,as you raise the temperature to millions of degrees.

The greater the wavelength of light,the greater its energy.

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

Telescopes: Portals of Discovery

Our Planetary System

Formation of the Solar System

Planetary Geology: Earth and the Other Terrestrial Worlds

Planetary Atmospheres: Earth and the Other Terrestrial Worlds

Jovian Planet Systems

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 Birth

Star Stuff

The Bizarre Stellar Graveyard

Our Galaxy

Galaxies and the Foundations of Modern Cosmology

Galaxy Evolution

The Birth of the Universe

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

Life in the Universe

Celestial Timekeeping and Navigation

Space and Time

Spacetime and Gravity

Building Blocks of the Universe

Filters