Question 1

A spectrum that displays a smooth variation in intensity over a range of wavelengths with breaks where no energy is observed at specific wavelengths is a(n) ____ spectrum.

Accepted Answer

A)  absorption 
B)  emission 
C)  continuous 
D)  Doppler 
E)  ionization 
A)  absorption 
B)  emission 
C)  continuous 
D)  Doppler 
E)  ionization A

Question 2

A hot object that is glowing orange will become redder as it cools.

Accepted Answer

A) True 
 B)False  True

Question 3

During the first year of its operation, only 20% of the projects scheduled for the Hubble Space Telescope involved taking images and pictures of celestial objects. The remaining 80% of the telescope's time was devoted to observing the spectrum of celestial objects. 
Why do astronomers place such a high emphasis on looking at the spectrum of a celestial object rather than an image? Explain.

Accepted Answer

Some important information about the shape, size and physical nature of an object can be determined from an image. The analysis of an object's spectrum can yield more important information, even if the object is too small or distant for any shape or size to be determined. 
Using Wien's law, a continuous or absorption spectrum can be used to find the surface temperature of an object based purely on the pattern of energy emitted at different wavelengths. 
The position of spectral lines in an absorption or emission spectrum is a reliable way to identify chemical elements that are present in or around the object. In some cases, the relative amount of the different elements can also be determined. 
If the pattern of spectral lines is shifted from what is expected as a result of the Doppler effect, the motion of the object toward, or away from the observer can be determined. 
All of these things can be determined simply by looking at the distribution of photons of different wavelengths coming from an object - the object's spectrum. Since the photons travel to the observer, it is not necessary for the observer to travel to the source for these observations. This is a great advantage, since astronomical distances are too large to permit travel to the objects themselves.

Question 4

Photons of light can be absorbed by an atom of an element ____.

Accepted Answer

A)  if they match one of several possible wavelengths that are absorbed by that element 
B)  if they match one of several possible wavelengths that are absorbed by all elements 
C)  if they match the only particular wavelength that can be absorbed by that element 
D)  if they match the only particular wavelength that can be absorbed by all elements 
E)  no matter what wavelength they have 
A)  if they match one of several possible wavelengths that are absorbed by that element 
B)  if they match one of several possible wavelengths that are absorbed by all elements 
C)  if they match the only particular wavelength that can be absorbed by that element 
D)  if they match the only particular wavelength that can be absorbed by all elements 
E)  no matter what wavelength they have

Question 5

A neutral atom must have ____.

Accepted Answer

A)  an equal number of protons and neutrons 
B)  an equal number of protons and electrons 
C)  an equal number of neutrons and electrons 
D)  less electrons than protons 
E)  more electrons than neutrons 
A)  an equal number of protons and neutrons 
B)  an equal number of protons and electrons 
C)  an equal number of neutrons and electrons 
D)  less electrons than protons 
E)  more electrons than neutrons

Question 6

A spectrum that displays no energy except at very specific wavelengths where intense radiation is observed is a(n) ____ spectrum.

Accepted Answer

A)  absorption 
B)  emission 
C)  continuous 
D)  Doppler 
E)  ionization 
A)  absorption 
B)  emission 
C)  continuous 
D)  Doppler 
E)  ionization

Question 7

A shift in the position of an emission line of an element toward the red or blue is produced by ____.

Accepted Answer

A)  atoms that become ionized 
B)  electrons that transfer from a high energy level to a low energy level 
C)  electrons that transfer from a low energy level to a high energy level 
D)  the intensity of agitation of atoms in a hot gas 
E)  the motion of an object toward or away from the observer 
A)  atoms that become ionized 
B)  electrons that transfer from a high energy level to a low energy level 
C)  electrons that transfer from a low energy level to a high energy level 
D)  the intensity of agitation of atoms in a hot gas 
E)  the motion of an object toward or away from the observer

Question 8

If you move an electron from the ground state to a higher energy level, the atom becomes an excited atom.

Accepted Answer

A) True 
 B)False

Question 9

The Doppler effect is useful in measuring the ____.

Accepted Answer

A)  distance to an object 
B)  chemical composition of an object 
C)  temperature of an object 
D)  motion of an object across the line of sight of an observer 
E)  motion of an object toward or away from the observer 
A)  distance to an object 
B)  chemical composition of an object 
C)  temperature of an object 
D)  motion of an object across the line of sight of an observer 
E)  motion of an object toward or away from the observer

Question 10

If    expresses the relationship between Kelvin temperature and the wavelength of maximum intensity in nanometers, what is the wavelength in nanometers of maximum intensity for a star with a surface temperature of 7,250K?

Accepted Answer

400,400 nm

Question 11

The binding energy is the amount of energy ____.

Accepted Answer

A)  needed to pull a proton completely away from the nucleus 
B)  needed to pull an electron completely away from the nucleus 
C)  needed to push a neutron into the nucleus 
D)  needed to completely separate all particles in the atom 
E)  necessary to move a proton to a permitted orbit 
A)  needed to pull a proton completely away from the nucleus 
B)  needed to pull an electron completely away from the nucleus 
C)  needed to push a neutron into the nucleus 
D)  needed to completely separate all particles in the atom 
E)  necessary to move a proton to a permitted orbit

Question 12

The agitation of atoms in a hot body creates a continuous spectrum of radiation.

Accepted Answer

A) True 
 B)False

Question 13

An object that acts as a blackbody emits photons because ____.

Accepted Answer

A)  thermal energy excites electrons to the ground state 
B)  electrons in the atoms of the object jump to lower energy levels 
C)  electrons in the atoms of the object jump to higher energy levels 
D)  atoms in the object collide, changing the motion of charged particles 
E)  atoms in the object have absorbed photons from an external source 
A)  thermal energy excites electrons to the ground state 
B)  electrons in the atoms of the object jump to lower energy levels 
C)  electrons in the atoms of the object jump to higher energy levels 
D)  atoms in the object collide, changing the motion of charged particles 
E)  atoms in the object have absorbed photons from an external source

Question 14

Blackbody radiation is caused by an object's ____.

Accepted Answer

A)  chemical structure 
B)  binding energy 
C)  excitation level 
D)  absolute zero 
E)  thermal agitation 
A)  chemical structure 
B)  binding energy 
C)  excitation level 
D)  absolute zero 
E)  thermal agitation

Question 15

In blackbody radiation, short-wavelength and long-wavelength photons are rare.

Accepted Answer

A) True 
 B)False

Question 16

Name the three subatomic particles that make up an atom and state their electrical charges

Accepted Answer

Protons - have a pos

Question 17

A continuous spectrum is produced by ____.

Accepted Answer

A)  atoms that become ionized 
B)  electrons that transfer from a high energy level to a low energy level 
C)  electrons that transfer from a low energy level to a high energy level 
D)  the intensity of agitation of atoms in a hot gas 
E)  the motion of an object toward or away from the observer 
A)  atoms that become ionized 
B)  electrons that transfer from a high energy level to a low energy level 
C)  electrons that transfer from a low energy level to a high energy level 
D)  the intensity of agitation of atoms in a hot gas 
E)  the motion of an object toward or away from the observer

Question 18

The formula     expresses the relationship between Kelvin temperature and the amount of radiated energy. If a star is three times the temperature of the Sun, how many times more intense is the energy radiated from an equal-sized area of its surface? (Answer with a number only.

Accepted Answer

The answer of The formula     expresses the...

Question 19

An atom that has lost or gained one or more electrons is called a(n) ____.

Accepted Answer

A)  ion 
B)  isotope 
C)  nucleus 
D)  molecule 
E)  electron 
A)  ion 
B)  isotope 
C)  nucleus 
D)  molecule 
E)  electron

Question 20

The Doppler formula states that the ratio of the velocity of a source to the speed of light is equal to the ratio of the change in wavelength caused by the Doppler shift to the source wavelength, or   A spacecraft has yellow headlights which radiate 600nm photons, and is travelling toward a stationary observer. If the spacecraft is travelling at a velocity of 1% of the speed of light (0.01c), what will be the amount of the shift in wavelength observed (in nanometers)?

Accepted Answer

The answer of The Doppler formula states that the ratio...

Exam 7: Atoms and Spectra

A spectrum that displays a smooth variation in intensity over a range of wavelengths with breaks where no energy is observed at specific wavelengths is a(n) ____ spectrum.

A hot object that is glowing orange will become redder as it cools.

Photons of light can be absorbed by an atom of an element ____.

A neutral atom must have ____.

A spectrum that displays no energy except at very specific wavelengths where intense radiation is observed is a(n) ____ spectrum.

A shift in the position of an emission line of an element toward the red or blue is produced by ____.

If you move an electron from the ground state to a higher energy level, the atom becomes an excited atom.

The Doppler effect is useful in measuring the ____.

If expresses the relationship between Kelvin temperature and the wavelength of maximum intensity in nanometers, what is the wavelength in nanometers of maximum intensity for a star with a surface temperature of 7,250K?

The binding energy is the amount of energy ____.

The agitation of atoms in a hot body creates a continuous spectrum of radiation.

An object that acts as a blackbody emits photons because ____.

Blackbody radiation is caused by an object's ____.

In blackbody radiation, short-wavelength and long-wavelength photons are rare.

Name the three subatomic particles that make up an atom and state their electrical charges

A continuous spectrum is produced by ____.

The formula expresses the relationship between Kelvin temperature and the amount of radiated energy. If a star is three times the temperature of the Sun, how many times more intense is the energy radiated from an equal-sized area of its surface? (Answer with a number only.

An atom that has lost or gained one or more electrons is called a(n) ____.

Here and Now

A Users Guide to the Sky

Moon Phases and Eclipses

Origins of Modern Astronomy

Gravity

Light and Telescopes

The Sun

The Family of Stars

The Interstellar Medium

Formation and Structure of Stars

Stellar Evolution

Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies

Supermassive Black Holes and Active Galaxies

Modern Cosmology

Origin of the Solar System and Extrasolar Planets

Earth the Active Planet

The Moon and Mercury

Venus and Mars

Jupiter and Saturn

Uranus Neptune Pluto and the Kuiper Belt

Meteorites Asteroids and Comets

Astrobiology

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