Question 1

Which of the following statements about electrical charge is true?

Accepted Answer

A) Two negative charges will attract each other. 
B) Two positive charges will attract each other. 
C) A positive charge and a negative charge will repel each other. 
D) A positive charge and a negative charge will attract each other. 
A) Two negative charges will attract each other. 
B) Two positive charges will attract each other. 
C) A positive charge and a negative charge will repel each other. 
D) A positive charge and a negative charge will attract each other.

Question 2

Suppose you look at a spectrum of visible light by looking through a prism or diffraction grating.How can you decide whether it is an emission line spectrum or an absorption line spectrum?

Accepted Answer

A) An emission line spectrum consists of bright lines on a dark background,while an absorption line spectrum consists of dark lines on a rainbow background. 
B) An emission line spectrum consists of a long bright line,while an absorption line spectrum consists of a long dark line. 
C) The only way to decide is to make a graph of the intensity of the light at every wavelength,and then analyze the graph carefully. 
D) The emission line spectrum is produced by electrons jumping up in energy level,while the absorption line spectrum is produced by electrons jumping down in energy level. 
A) An emission line spectrum consists of bright lines on a dark background,while an absorption line spectrum consists of dark lines on a rainbow background. 
B) An emission line spectrum consists of a long bright line,while an absorption line spectrum consists of a long dark line. 
C) The only way to decide is to make a graph of the intensity of the light at every wavelength,and then analyze the graph carefully. 
D) The emission line spectrum is produced by electrons jumping up in energy level,while the absorption line spectrum is produced by electrons jumping down in energy level.

Question 3

If we observe one edge of a star to be redshifted and the opposite edge to be blueshifted,what can we conclude about the star?

Accepted Answer

A) The star is actually two bodies,one moving toward us,the other away from us. 
B) The star is in the process of falling apart. 
C) The star is in the process of formation. 
D) The star is rotating. 
E) The star's surface is very different from one side to the other. 
A) The star is actually two bodies,one moving toward us,the other away from us. 
B) The star is in the process of falling apart. 
C) The star is in the process of formation. 
D) The star is rotating. 
E) The star's surface is very different from one side to the other.

Question 4

X-rays always have more energy than radio waves.

Accepted Answer

A) True 
 B)False

Question 5

The spectra of most galaxies show redshifts.This means that their spectral lines

Accepted Answer

A) have wavelengths that are longer than normal. 
B) always are in the red part of the visible spectrum. 
C) have wavelengths that are shorter than normal. 
D) have a higher intensity in the red part of the spectrum. 
A) have wavelengths that are longer than normal. 
B) always are in the red part of the visible spectrum. 
C) have wavelengths that are shorter than normal. 
D) have a higher intensity in the red part of the spectrum.

Question 6

The spectra of most galaxies show redshifts.This means that their spectral lines

Accepted Answer

A) always are in the red part of the visible spectrum. 
B) have wavelengths that are longer than normal. 
C) have wavelengths that are shorter than normal. 
D) have a higher intensity in the red part of the spectrum. 
E) have normal wavelengths,but absorption of light makes them appear red. 
A) always are in the red part of the visible spectrum. 
B) have wavelengths that are longer than normal. 
C) have wavelengths that are shorter than normal. 
D) have a higher intensity in the red part of the spectrum. 
E) have normal wavelengths,but absorption of light makes them appear red.

Question 7

Which of the following conditions lead you to see an absorption line spectrum from a cloud of gas in interstellar space?

Accepted Answer

A) The cloud is extremely hot. 
B) The cloud is visible primarily because it reflects light from nearby stars. 
C) The cloud is cool and very dense,so that you cannot see any objects that lie behind it. 
D) The cloud is cool and lies between you and a hot star. 
A) The cloud is extremely hot. 
B) The cloud is visible primarily because it reflects light from nearby stars. 
C) The cloud is cool and very dense,so that you cannot see any objects that lie behind it. 
D) The cloud is cool and lies between you and a hot star.

Question 8

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

Question 9

There are more atoms in a glass of water than stars in the observable universe.

Accepted Answer

A) True 
 B)False

Question 10

An atom that has fewer electrons than protons is called a/an

Accepted Answer

A) molecule. 
B) solid. 
C) ion. 
D) plasma. 
A) molecule. 
B) solid. 
C) ion. 
D) plasma.

Question 11

Which of the following statements is true of green grass?

Accepted Answer

A) It absorbs red light and emits green light. 
B) It absorbs red light and reflects green light. 
C) It transmits all colors of light except green. 
D) It means the lawn is healthy. 
A) It absorbs red light and emits green light. 
B) It absorbs red light and reflects green light. 
C) It transmits all colors of light except green. 
D) It means the lawn is healthy.

Question 12

Suppose you had molecular oxygen (O₂)chilled enough so that it was in liquid form.Which of the following best describes the phase changes that would occur as you heated the liquid oxygen to high temperature?

Accepted Answer

A) It would evaporate into a gas,then the molecules would dissociate into individual oxygen atoms,then the atoms would become increasingly ionized as you continued to raise the temperature. 
B) The liquid molecules would quickly dissociate into a liquid of individual oxygen atoms.These atoms would then evaporate into a gas,and then become ionized to make a plasma. 
C) It would vaporize into a gas,then the molecules would lose electrons until no electrons were left,then the molecules would dissociate into individual oxygen nuclei. 
D) The cold temperature would first cause the oxygen to solidify.The solid would then sublimate into a gas,which would then become a plasma as the molecules lost their electrons,until finally it consisted of bonded pairs of oxygen nuclei stripped bare of any electrons. 
A) It would evaporate into a gas,then the molecules would dissociate into individual oxygen atoms,then the atoms would become increasingly ionized as you continued to raise the temperature. 
B) The liquid molecules would quickly dissociate into a liquid of individual oxygen atoms.These atoms would then evaporate into a gas,and then become ionized to make a plasma. 
C) It would vaporize into a gas,then the molecules would lose electrons until no electrons were left,then the molecules would dissociate into individual oxygen nuclei. 
D) The cold temperature would first cause the oxygen to solidify.The solid would then sublimate into a gas,which would then become a plasma as the molecules lost their electrons,until finally it consisted of bonded pairs of oxygen nuclei stripped bare of any electrons.

Question 13

Process of Science: I am doing science when I already know the answer to my scientific question and I am searching for evidence in the natural world strictly to support what I know.

Accepted Answer

A) True 
 B)False

Question 14

Without telescopes or other aid,we can see the Moon because it

Accepted Answer

A) emits visible light. 
B) emits thermal radiation. 
C) reflects infrared light. 
D) reflects visible light. 
E) glows through radioactive decay. 
A) emits visible light. 
B) emits thermal radiation. 
C) reflects infrared light. 
D) reflects visible light. 
E) glows through radioactive decay.

Question 15

Betelgeuse is the bright red star representing the left shoulder of the constellation Orion.All the following statements about Betelgeuse are true.Which one can you infer from its red color?

Accepted Answer

A) It is much brighter than the Sun. 
B) Its surface is cooler than the surface of the Sun. 
C) It is much more massive than the Sun. 
D) It is moving away from us. 
A) It is much brighter than the Sun. 
B) Its surface is cooler than the surface of the Sun. 
C) It is much more massive than the Sun. 
D) It is moving away from us.

Question 16

Which of the following best describes the fundamental difference between two different chemical elements (such as oxygen and carbon)?

Accepted Answer

A) They have different atomic mass numbers. 
B) They have different numbers of protons in their nucleus. 
C) They have different numbers of electrons. 
D) They have different names. 
A) They have different atomic mass numbers. 
B) They have different numbers of protons in their nucleus. 
C) They have different numbers of electrons. 
D) They have different names.

Question 17

Which of the following statements about X-rays and radio waves is not true?

Accepted Answer

A) Neither X-rays nor radio waves can penetrate the earth's atmosphere. 
B) X-rays have shorter wavelengths than radio waves. 
C) X-rays and radio waves are both forms of light,or electromagnetic radiation. 
D) X-rays have higher frequency than radio waves. 
E) X-rays have higher energy than radio waves. 
A) Neither X-rays nor radio waves can penetrate the earth's atmosphere. 
B) X-rays have shorter wavelengths than radio waves. 
C) X-rays and radio waves are both forms of light,or electromagnetic radiation. 
D) X-rays have higher frequency than radio waves. 
E) X-rays have higher energy than radio waves.

Question 18

Briefly explain how we can use spectral lines to determine an object's radial motion.Can we also learn the object's tangential motion (across our line of sight)from its spectral lines?

Accepted Answer

By comparing the wavelength of the spect

Question 19

From shortest to longest wavelength,which of the following correctly orders the different categories of electromagnetic radiation?

Accepted Answer

A) gamma rays,X-rays,ultraviolet,visible light,infrared,radio 
B) infrared,visible light,ultraviolet,X-rays,gamma rays,radio 
C) radio,infrared,visible light,ultraviolet,X-rays,gamma rays 
D) gamma rays,X-rays,visible light,ultraviolet,infrared,radio 
A) gamma rays,X-rays,ultraviolet,visible light,infrared,radio 
B) infrared,visible light,ultraviolet,X-rays,gamma rays,radio 
C) radio,infrared,visible light,ultraviolet,X-rays,gamma rays 
D) gamma rays,X-rays,visible light,ultraviolet,infrared,radio

Question 20

Which of the following statements about electrons is not true?

Accepted Answer

A) Electrons orbit the nucleus rather like planets orbiting the Sun. 
B) Within an atom,an electron can have only particular energies. 
C) An electron has a negative electrical charge. 
D) Electrons have very little mass compared to protons or neutrons. 
E) Electrons can jump between energy levels in an atom only if they receive or give up an amount of energy equal to the difference in energy between the energy levels. 
A) Electrons orbit the nucleus rather like planets orbiting the Sun. 
B) Within an atom,an electron can have only particular energies. 
C) An electron has a negative electrical charge. 
D) Electrons have very little mass compared to protons or neutrons. 
E) Electrons can jump between energy levels in an atom only if they receive or give up an amount of energy equal to the difference in energy between the energy levels.

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

Which of the following statements about electrical charge is true?

Suppose you look at a spectrum of visible light by looking through a prism or diffraction grating.How can you decide whether it is an emission line spectrum or an absorption line spectrum?

If we observe one edge of a star to be redshifted and the opposite edge to be blueshifted,what can we conclude about the star?

X-rays always have more energy than radio waves.

The spectra of most galaxies show redshifts.This means that their spectral lines

The spectra of most galaxies show redshifts.This means that their spectral lines

Which of the following conditions lead you to see an absorption line spectrum from a cloud of gas in interstellar space?

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

There are more atoms in a glass of water than stars in the observable universe.

An atom that has fewer electrons than protons is called a/an

Which of the following statements is true of green grass?

Suppose you had molecular oxygen (O₂)chilled enough so that it was in liquid form.Which of the following best describes the phase changes that would occur as you heated the liquid oxygen to high temperature?

Process of Science: I am doing science when I already know the answer to my scientific question and I am searching for evidence in the natural world strictly to support what I know.

Without telescopes or other aid,we can see the Moon because it

Betelgeuse is the bright red star representing the left shoulder of the constellation Orion.All the following statements about Betelgeuse are true.Which one can you infer from its red color?

Which of the following best describes the fundamental difference between two different chemical elements (such as oxygen and carbon)?

Which of the following statements about X-rays and radio waves is not true?

Briefly explain how we can use spectral lines to determine an object's radial motion.Can we also learn the object's tangential motion (across our line of sight)from its spectral lines?

From shortest to longest wavelength,which of the following correctly orders the different categories of electromagnetic radiation?

Which of the following statements about electrons is not true?

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