Question 1

An astronomer measures the spectrum of a star and finds that it emits the most intense light at 0.5 mm.What is its temperature?

Accepted Answer

A)  1,000 K 
B)  3,000 K 
C)  6,000 K 
D)  9,000 K 
A)  1,000 K 
B)  3,000 K 
C)  6,000 K 
D)  9,000 K

Question 2

Which of the following portions of the electromagnetic spectrum must be observed from space?

Accepted Answer

A)  ultraviolet 
B)  radio 
C)  near infrared 
D)  visible 
A)  ultraviolet 
B)  radio 
C)  near infrared 
D)  visible

Question 3

The figure below shows a model of an atom.If an electron begins in orbit #1,moves to orbit #4,then moves to orbit #3,and then to orbit #1,how has it interacted with light?

Accepted Answer

A)  It has emitted a high energy photon and absorbed two low energy photons. 
B)  It has absorbed a high energy photon and emitted two low energy photons. 
C)  It has absorbed a photon and emitted two photons, all with identical energies. 
D)  It has emitted a photon and absorbed two photons, all with identical energies. 
A)  It has emitted a high energy photon and absorbed two low energy photons. 
B)  It has absorbed a high energy photon and emitted two low energy photons. 
C)  It has absorbed a photon and emitted two photons, all with identical energies. 
D)  It has emitted a photon and absorbed two photons, all with identical energies.

Question 4

Modern astronomical observatories sometimes shine lasers into the sky because they:

Accepted Answer

A)  help guide the pointing of the telescope. 
B)  allow corrections of atmospheric turbulence. 
C)  decrease the atmospheric opacity. 
D)  calibrate spectroscopes. 
A)  help guide the pointing of the telescope. 
B)  allow corrections of atmospheric turbulence. 
C)  decrease the atmospheric opacity. 
D)  calibrate spectroscopes.

Question 5

Stars twinkle because of:

Accepted Answer

A)  interstellar dust. 
B)  surface variations on the stars. 
C)  atmospheric turbulence. 
D)  opacity variations. 
A)  interstellar dust. 
B)  surface variations on the stars. 
C)  atmospheric turbulence. 
D)  opacity variations.

Question 6

The H alpha line of hydrogen produces photons in what part of the electromagnetic spectrum?

Accepted Answer

A)  ultraviolet 
B)  blue 
C)  red 
D)  infrared 
A)  ultraviolet 
B)  blue 
C)  red 
D)  infrared

Question 7

How would you use a star's spectrum to measure its temperature?

Accepted Answer

The wavelength at which the co

Question 8

Two stars are situated a distance 1 parsec apart.Both are a distance of 100 parsecs from Earth,as shown in the figure below.An astronomer would like to observe these stars individually with a radio telescope.Find the minimum diameter of her telescope if she decides to observe the stars at a wavelength of 1 m.

Accepted Answer

The answer of Two stars are situated a distance 1...

Question 9

What property of a star allows you to measure its composition?

Accepted Answer

A)  the brightest color in its spectrum 
B)  the wavelengths of its absorption lines 
C)  its luminosity 
D)  its mass 
A)  the brightest color in its spectrum 
B)  the wavelengths of its absorption lines 
C)  its luminosity 
D)  its mass

Question 10

What does thermal energy represent?

Accepted Answer

Thermal energy is th

Question 11

The Lyman series refers to:

Accepted Answer

A)  the photons produced as an electron makes a series of jumps from a high excited state to the ground state of hydrogen. 
B)  the discrete orbits in the hydrogen atom. 
C)  electronic transitions between the ground state and excited states of hydrogen. 
D)  electronic transitions in the hydrogen atom that produce light in the visible part of the spectrum. 
A)  the photons produced as an electron makes a series of jumps from a high excited state to the ground state of hydrogen. 
B)  the discrete orbits in the hydrogen atom. 
C)  electronic transitions between the ground state and excited states of hydrogen. 
D)  electronic transitions in the hydrogen atom that produce light in the visible part of the spectrum.

Question 12

Two light waves have wavelengths of 200 nm and 400 nm,respectively.How are their frequencies related?

Accepted Answer

A)  The wave with a 200 nm wavelength has one-quarter the frequency of the 400 nm wave. 
B)  The wave with a 200 nm wavelength has one-half the frequency of the 400 nm wave. 
C)  The wave with a 200 nm wavelength has the same frequency of the 400 nm wave. 
D)  The wave with a 200 nm wavelength has twice the frequency of the 400 nm wave. 
A)  The wave with a 200 nm wavelength has one-quarter the frequency of the 400 nm wave. 
B)  The wave with a 200 nm wavelength has one-half the frequency of the 400 nm wave. 
C)  The wave with a 200 nm wavelength has the same frequency of the 400 nm wave. 
D)  The wave with a 200 nm wavelength has twice the frequency of the 400 nm wave.

Question 13

A wave in the electromagnetic field is:

Accepted Answer

A)  light. 
B)  an electron. 
C)  radioactivity. 
D)  an ion. 
A)  light. 
B)  an electron. 
C)  radioactivity. 
D)  an ion.

Question 14

Place the following varieties of light in order,from lowest to highest frequency: infrared,ultraviolet,microwave,visible,gamma rays.

Accepted Answer

A)  infrared, gamma ray, ultraviolet, visible, microwave 
B)  microwave, infrared, visible, ultraviolet, gamma ray 
C)  gamma ray, ultraviolet, infrared, visible, microwave 
D)  infrared, visible, microwave, ultraviolet, gamma ray 
A)  infrared, gamma ray, ultraviolet, visible, microwave 
B)  microwave, infrared, visible, ultraviolet, gamma ray 
C)  gamma ray, ultraviolet, infrared, visible, microwave 
D)  infrared, visible, microwave, ultraviolet, gamma ray

Question 15

Which of the following is NOT an advantage of a reflecting telescope over a refracting telescope?

Accepted Answer

A)  Mirrors suffer less chromatic aberration than lenses. 
B)  Reflecting telescopes can be made shorter than refracting telescopes. 
C)  Mirrors provide stronger magnification than lenses. 
D)  Reflecting telescopes can support larger mirrors. 
A)  Mirrors suffer less chromatic aberration than lenses. 
B)  Reflecting telescopes can be made shorter than refracting telescopes. 
C)  Mirrors provide stronger magnification than lenses. 
D)  Reflecting telescopes can support larger mirrors.

Question 16

A spectrograph measures the:

Accepted Answer

A)  speed of a light beam. 
B)  energy carried by each component wavelength of a light beam. 
C)  polarization of a light beam. 
D)  atmospheric distortion experienced by a light beam. 
A)  speed of a light beam. 
B)  energy carried by each component wavelength of a light beam. 
C)  polarization of a light beam. 
D)  atmospheric distortion experienced by a light beam.

Question 17

The next generation of large near-infrared telescopes will be built at high,dry sites.List two reasons why.

Accepted Answer

First,high,dry sites have very little wa

Question 18

If your pupil is 1 cm across,how large does a telescope aperture have to be to collect one million times more light than your eye?

Accepted Answer

A)  10 cm 
B)  1 m 
C)  10 m 
D)  100 m 
A)  10 cm 
B)  1 m 
C)  10 m 
D)  100 m

Question 19

Consider the experiment shown in the figure below.Describe the spectra observed by Spectrographs A,B,and C.

Accepted Answer

Spectrograph A observes an absorption sp

Question 20

An astronomer takes spectra of two stars,A and B.Star A's spectrum peaks at 200 nm,while star B's spectrum peaks at 800 nm.If the stars have identical sizes,how do their luminosities compare?

Accepted Answer

Star A is

An astronomer measures the spectrum of a star and finds that it emits the most intense light at 0.5 mm.What is its temperature?

Which of the following portions of the electromagnetic spectrum must be observed from space?

The figure below shows a model of an atom.If an electron begins in orbit #1,moves to orbit #4,then moves to orbit #3,and then to orbit #1,how has it interacted with light?

Modern astronomical observatories sometimes shine lasers into the sky because they:

Stars twinkle because of:

The H alpha line of hydrogen produces photons in what part of the electromagnetic spectrum?

How would you use a star's spectrum to measure its temperature?

What property of a star allows you to measure its composition?

What does thermal energy represent?

The Lyman series refers to:

Two light waves have wavelengths of 200 nm and 400 nm,respectively.How are their frequencies related?

A wave in the electromagnetic field is:

Place the following varieties of light in order,from lowest to highest frequency: infrared,ultraviolet,microwave,visible,gamma rays.

Which of the following is NOT an advantage of a reflecting telescope over a refracting telescope?

A spectrograph measures the:

The next generation of large near-infrared telescopes will be built at high,dry sites.List two reasons why.

If your pupil is 1 cm across,how large does a telescope aperture have to be to collect one million times more light than your eye?

Consider the experiment shown in the figure below.Describe the spectra observed by Spectrographs A,B,and C.

An astronomer takes spectra of two stars,A and B.Star A's spectrum peaks at 200 nm,while star B's spectrum peaks at 800 nm.If the stars have identical sizes,how do their luminosities compare?

Getting Started: Science, astronomy, and Being Human

A Universe Made, a Universe Discovered

A Universe of Universal Laws

The Architecture and Birth of Planetary Systems

Home Base: Earth and Moon

Sibling Worlds: Mercury, Venus, and Mars

Gas, ice, and Stone: the Outer Planets

Life and the Search for Habitable Worlds

The Sun As a Star

Measuring the Stars: the Main Sequence and Its Meaning

Nursery of the Stars: the Interstellar Medium and Star Formation

To the Graveyard of Stars: the End Points of Stellar Evolution

Down the Rabbit Hole: Relativity and Black Holes

Our City of Stars: the Milky Way

A Universe of Galaxies

The Cosmic Web: the Large-Scale Structure of the Universe

Cosmology

Filters

Exam 4: A Universe of Universal Laws

An astronomer measures the spectrum of a star and finds that it emits the most intense light at 0.5 mm.What is its temperature?

Which of the following portions of the electromagnetic spectrum must be observed from space?

The figure below shows a model of an atom.If an electron begins in orbit #1,moves to orbit #4,then moves to orbit #3,and then to orbit #1,how has it interacted with light?

Modern astronomical observatories sometimes shine lasers into the sky because they:

Stars twinkle because of:

The H alpha line of hydrogen produces photons in what part of the electromagnetic spectrum?

How would you use a star's spectrum to measure its temperature?

What property of a star allows you to measure its composition?

What does thermal energy represent?

The Lyman series refers to:

Two light waves have wavelengths of 200 nm and 400 nm,respectively.How are their frequencies related?

A wave in the electromagnetic field is:

Place the following varieties of light in order,from lowest to highest frequency: infrared,ultraviolet,microwave,visible,gamma rays.

Which of the following is NOT an advantage of a reflecting telescope over a refracting telescope?

A spectrograph measures the:

The next generation of large near-infrared telescopes will be built at high,dry sites.List two reasons why.

If your pupil is 1 cm across,how large does a telescope aperture have to be to collect one million times more light than your eye?

Consider the experiment shown in the figure below.Describe the spectra observed by Spectrographs A,B,and C.

An astronomer takes spectra of two stars,A and B.Star A's spectrum peaks at 200 nm,while star B's spectrum peaks at 800 nm.If the stars have identical sizes,how do their luminosities compare?

Getting Started: Science, astronomy, and Being Human

A Universe Made, a Universe Discovered

A Universe of Universal Laws

The Architecture and Birth of Planetary Systems

Home Base: Earth and Moon

Sibling Worlds: Mercury, Venus, and Mars

Gas, ice, and Stone: the Outer Planets

Life and the Search for Habitable Worlds

The Sun As a Star

Measuring the Stars: the Main Sequence and Its Meaning

Nursery of the Stars: the Interstellar Medium and Star Formation

To the Graveyard of Stars: the End Points of Stellar Evolution

Down the Rabbit Hole: Relativity and Black Holes

Our City of Stars: the Milky Way

A Universe of Galaxies

The Cosmic Web: the Large-Scale Structure of the Universe

Cosmology

Filters