Question 1

Compare and contrast the wavelengths,frequencies,speeds,and energies of red and blue photons.

Accepted Answer

Red and blue photons both travel at the speed of light.Red photons have longer wavelengths,lower frequencies,and lower energy levels than those of blue photons.

Question 2

Arrays of radio telescopes can produce much better resolution than single-dish telescopes because they work based on the principle of:

Accepted Answer

A)  reflection. 
B)  refraction. 
C)  diffraction. 
D)  interference. 
A)  reflection. 
B)  refraction. 
C)  diffraction. 
D)  interference. D

Question 3

Explain two major advantages of CCDs over other imaging techniques.

Accepted Answer

Here are some possible answers:
(1)They have much higher quantum efficiency (~80 percent).
(2)Their photometric response is linearly proportional to the number of photons they collect.
(3)They yield output in digital format.
(4)They cover a wide spectral range (optical through near-infrared).
(5)They have a higher spatial resolution.

Question 4

Which properties of light changes in a refractive medium?

Accepted Answer

A)  wavelength 
B)  frequency, speed, and wavelength 
C)  wavelength and speed 
D)  speed 
A)  wavelength 
B)  frequency, speed, and wavelength 
C)  wavelength and speed 
D)  speed

Question 5

A red photon has a wavelength of 650 nm.An ultraviolet photon has a wavelength of 250 nm.The energy of an ultraviolet photon is ________ than a red photon.

Accepted Answer

A)  2.6 times larger 
B)  6.8 times larger 
C)  2.6 times smaller 
D)  6.8 times smaller 
A)  2.6 times larger 
B)  6.8 times larger 
C)  2.6 times smaller 
D)  6.8 times smaller

Question 6

The fact that the speed of light is constant (as it travels through a vacuum)means that:

Accepted Answer

A)  photons with longer wavelengths have lower frequencies. 
B)  radio wave photons have shorter wavelengths than gamma-ray photons. 
C)  X-rays can be transmitted through the atmosphere around the world. 
D)  All of the above are true. 
A)  photons with longer wavelengths have lower frequencies. 
B)  radio wave photons have shorter wavelengths than gamma-ray photons. 
C)  X-rays can be transmitted through the atmosphere around the world. 
D)  All of the above are true.

Question 7

The 305-meter Arecibo radio telescope in Puerto Rico has a resolution that is closest to that of:

Accepted Answer

A)  the Hubble Space Telescope (0.1 arcsec). 
B)  a human eye (1 arcmin). 
C)  the Chandra X-ray Telescope (0.5 arcsec). 
D)  a 1-meter optical telescope (1 arcsec). 
A)  the Hubble Space Telescope (0.1 arcsec). 
B)  a human eye (1 arcmin). 
C)  the Chandra X-ray Telescope (0.5 arcsec). 
D)  a 1-meter optical telescope (1 arcsec).

Question 8

Using the figure below,which type of electromagnetic wave has a frequency of approximately 3 × 10¹⁷ Hz?

Accepted Answer

A)  X-rays 
B)  infrared 
C)  microwave 
D)  radio 
A)  X-rays 
B)  infrared 
C)  microwave 
D)  radio

Question 9

The image below shows the Very Large Array in New Mexico.What is the benefit of using multiple telescopes in such an array?

Accepted Answer

Interferometry allows astronom

Question 10

Which of the following causes the biggest problem in detecting infrared photons from an astronomical object?

Accepted Answer

A)  smog 
B)  carbon dioxide 
C)  water vapor 
D)  light pollution 
A)  smog 
B)  carbon dioxide 
C)  water vapor 
D)  light pollution

Question 11

The angular resolution of the largest single-dish radio telescope in the United States,the 100 m Green Bank Telescope,is closest to________ when it operates at a wavelength of 20 cm.

Accepted Answer

A)  0.6° 
B)  0.6 arcmin 
C)  0.6 arcsec 
D)  6 arcsec 
A)  0.6° 
B)  0.6 arcmin 
C)  0.6 arcsec 
D)  6 arcsec

Question 12

When we determine the angular resolution of an interferometric array of radio telescopes using the formula q µ l/D,the variable D stands for the:

Accepted Answer

A)  diameter of the telescopes. 
B)  separation between the telescopes. 
C)  number of telescopes. 
D)  focal length of the telescopes. 
A)  diameter of the telescopes. 
B)  separation between the telescopes. 
C)  number of telescopes. 
D)  focal length of the telescopes.

Question 13

Before CCDs were invented,what was the device most commonly used for imaging with optical telescopes?

Accepted Answer

A)  Polaroid cameras 
B)  photographic glass plates 
C)  high-speed film 
D)  video cameras 
A)  Polaroid cameras 
B)  photographic glass plates 
C)  high-speed film 
D)  video cameras

Question 14

Explain why the largest telescopes are not refracting telescopes.

Accepted Answer

The larger the refracting tele

Question 15

Both reflecting and refracting telescopes suffer from:

Accepted Answer

A)  chromatic aberration. 
B)  diffraction effects and chromatic aberration. 
C)  greater increase in weight for a given increase in aperture. 
D)  diffraction effects. 
A)  chromatic aberration. 
B)  diffraction effects and chromatic aberration. 
C)  greater increase in weight for a given increase in aperture. 
D)  diffraction effects.

Question 16

The most important improvement that photography provides over naked-eye observations is:

Accepted Answer

A)  it is possible to observe a larger field of view with photographic plates. 
B)  the quantum efficiency is higher for photographic plates. 
C)  the image resolution is much better for photographic plates. 
D)  it is possible to detect fainter objects with the use of photographic plates. 
A)  it is possible to observe a larger field of view with photographic plates. 
B)  the quantum efficiency is higher for photographic plates. 
C)  the image resolution is much better for photographic plates. 
D)  it is possible to detect fainter objects with the use of photographic plates.

Question 17

What is the diffraction limit of a 4-meter telescope observing at a wavelength of 650 nm?

Accepted Answer

q = 2.06 × 10⁵ × (6.

Question 18

Which of the following photons carry the least amount of energy?

Accepted Answer

A)  a blue photon of the visible spectrum, whose wavelength is 450 nm 
B)  an infrared photon, whose wavelength is 10-5 meter 
C)  a red photon in the visible spectrum, whose wavelength is 700 nm 
D)  a microwave photon, whose wavelength is 10-2 meter 
A)  a blue photon of the visible spectrum, whose wavelength is 450 nm 
B)  an infrared photon, whose wavelength is 10-5 meter 
C)  a red photon in the visible spectrum, whose wavelength is 700 nm 
D)  a microwave photon, whose wavelength is 10-2 meter

Question 19

How does the speed of light traveling through a medium (such as air or glass)compare to the speed of light in a vacuum?

Accepted Answer

A)  It is the same as the speed of light in a vacuum. 
B)  It is always less than the speed of light in a vacuum. 
C)  It is always greater than the speed of light in a vacuum. 
D)  Sometimes it is greater than the speed of light in a vacuum, and sometimes it is less, depending on the medium. 
A)  It is the same as the speed of light in a vacuum. 
B)  It is always less than the speed of light in a vacuum. 
C)  It is always greater than the speed of light in a vacuum. 
D)  Sometimes it is greater than the speed of light in a vacuum, and sometimes it is less, depending on the medium.

Question 20

Which of the following properties is (are)improved by placing telescopes in space?

Accepted Answer

A)  quantum efficiency 
B)  integration time and angular resolution 
C)  quantum efficiency and integration time 
D)  ability to observe at multiple wavelength regions and angular resolution 
A)  quantum efficiency 
B)  integration time and angular resolution 
C)  quantum efficiency and integration time 
D)  ability to observe at multiple wavelength regions and angular resolution

Compare and contrast the wavelengths,frequencies,speeds,and energies of red and blue photons.

Arrays of radio telescopes can produce much better resolution than single-dish telescopes because they work based on the principle of:

Explain two major advantages of CCDs over other imaging techniques.

Which properties of light changes in a refractive medium?

A red photon has a wavelength of 650 nm.An ultraviolet photon has a wavelength of 250 nm.The energy of an ultraviolet photon is ________ than a red photon.

The fact that the speed of light is constant (as it travels through a vacuum)means that:

The 305-meter Arecibo radio telescope in Puerto Rico has a resolution that is closest to that of:

Using the figure below,which type of electromagnetic wave has a frequency of approximately 3 × 10¹⁷ Hz?

The image below shows the Very Large Array in New Mexico.What is the benefit of using multiple telescopes in such an array?

Which of the following causes the biggest problem in detecting infrared photons from an astronomical object?

The angular resolution of the largest single-dish radio telescope in the United States,the 100 m Green Bank Telescope,is closest to________ when it operates at a wavelength of 20 cm.

When we determine the angular resolution of an interferometric array of radio telescopes using the formula q µ l/D,the variable D stands for the:

Before CCDs were invented,what was the device most commonly used for imaging with optical telescopes?

Explain why the largest telescopes are not refracting telescopes.

Both reflecting and refracting telescopes suffer from:

The most important improvement that photography provides over naked-eye observations is:

What is the diffraction limit of a 4-meter telescope observing at a wavelength of 650 nm?

Which of the following photons carry the least amount of energy?

How does the speed of light traveling through a medium (such as air or glass)compare to the speed of light in a vacuum?

Which of the following properties is (are)improved by placing telescopes in space?

Thinking Like an Astronomer

Patterns in the Skymotions of Earth and the Moon

Laws of Motion

The Formation of Stars and Planets

Terrestrial Worlds in the Inner Solar System

Atmospheres of Venus, earth, and Mars

The Giant Planets

Small Bodies of the Solar System

Measuring the Stars

Our Star: the Sun

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Measuring Galaxies

Our Galaxy: the Milky Way

The Evolution of the Universe

Formation of Structure

Life in the Universe

Filters

Exam 4: Light and Telescopes

Compare and contrast the wavelengths,frequencies,speeds,and energies of red and blue photons.

Arrays of radio telescopes can produce much better resolution than single-dish telescopes because they work based on the principle of:

Explain two major advantages of CCDs over other imaging techniques.

Which properties of light changes in a refractive medium?

A red photon has a wavelength of 650 nm.An ultraviolet photon has a wavelength of 250 nm.The energy of an ultraviolet photon is ________ than a red photon.

The fact that the speed of light is constant (as it travels through a vacuum)means that:

The 305-meter Arecibo radio telescope in Puerto Rico has a resolution that is closest to that of:

Using the figure below,which type of electromagnetic wave has a frequency of approximately 3 × 10¹⁷ Hz?

The image below shows the Very Large Array in New Mexico.What is the benefit of using multiple telescopes in such an array?

Which of the following causes the biggest problem in detecting infrared photons from an astronomical object?

The angular resolution of the largest single-dish radio telescope in the United States,the 100 m Green Bank Telescope,is closest to________ when it operates at a wavelength of 20 cm.

When we determine the angular resolution of an interferometric array of radio telescopes using the formula q µ l/D,the variable D stands for the:

Before CCDs were invented,what was the device most commonly used for imaging with optical telescopes?

Explain why the largest telescopes are not refracting telescopes.

Both reflecting and refracting telescopes suffer from:

The most important improvement that photography provides over naked-eye observations is:

What is the diffraction limit of a 4-meter telescope observing at a wavelength of 650 nm?

Which of the following photons carry the least amount of energy?

How does the speed of light traveling through a medium (such as air or glass)compare to the speed of light in a vacuum?

Which of the following properties is (are)improved by placing telescopes in space?

Thinking Like an Astronomer

Patterns in the Skymotions of Earth and the Moon

Laws of Motion

The Formation of Stars and Planets

Terrestrial Worlds in the Inner Solar System

Atmospheres of Venus, earth, and Mars

The Giant Planets

Small Bodies of the Solar System

Measuring the Stars

Our Star: the Sun

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Measuring Galaxies

Our Galaxy: the Milky Way

The Evolution of the Universe

Formation of Structure

Life in the Universe

Filters