Question 1

Compared to a smaller objective lens,a larger objective lens makes a star's image ...

Accepted Answer

A)  brighter 
B)  dimmer 
C)  no effect 
A)  brighter 
B)  dimmer 
C)  no effect A

Question 2

What statement below best describes the behavior of light encountering the objective lens of a refracting telescope?

Accepted Answer

A)  All light is absorbed as it travels though a dense,transparent material. 
B)  White light from astronomical objects is emitted by the lens. 
C)  Light rays are focussed to form an image after they pass through the lens which is of different optical density. 
D)  Light rays are focussed to form an image after they reflect off the lens. 
A)  All light is absorbed as it travels though a dense,transparent material. 
B)  White light from astronomical objects is emitted by the lens. 
C)  Light rays are focussed to form an image after they pass through the lens which is of different optical density. 
D)  Light rays are focussed to form an image after they reflect off the lens. C

Question 3

An ordinary glass lens forms an image by ____________ of light.

Accepted Answer

A)  reflection 
B)  refraction 
C)  diffraction 
A)  reflection 
B)  refraction 
C)  diffraction B

Question 4

Which has the larger light-gathering power?

Accepted Answer

A)  A telescope of 5 cm diameter and focal length of 50 cm. 
B)  A telescope of 6 cm diameter and focal length of 100 cm. 
C)  A telescope of 2 cm diameter and focal length of 100 cm. 
D)  A telescope of 3 cm diameter and focal length of 75 cm. 
E)  Both b and c since they have the same focal length 
A)  A telescope of 5 cm diameter and focal length of 50 cm. 
B)  A telescope of 6 cm diameter and focal length of 100 cm. 
C)  A telescope of 2 cm diameter and focal length of 100 cm. 
D)  A telescope of 3 cm diameter and focal length of 75 cm. 
E)  Both b and c since they have the same focal length

Question 5

Reflecting telescopes are no longer popular with astronomers because they are expensive and suffer from chromatic aberration.

Accepted Answer

A) True 
 B)False

Question 6

The amount of energy a photon carries depends on its wavelength.

Accepted Answer

A) True 
 B)False

Question 7

A(n)____________________ is used to measure the brightness and color of stars.

Accepted Answer

The answer of A(n)____________________ is used to measure the brightness...

Question 8

____ has (have)wavelengths that are shorter than visible light.

Accepted Answer

A)  Gamma-rays 
B)  Ultraviolet light 
C)  Infrared radiation 
D)  Radio 
E)  a and b 
A)  Gamma-rays 
B)  Ultraviolet light 
C)  Infrared radiation 
D)  Radio 
E)  a and b

Question 9

Infra-red space telescopes must have their mirror cooled to very low temperatures because otherwise it would thermally emit too much ____ itself.

Accepted Answer

A)  infra-red radiation 
B)  radio waves 
C)  X-waves 
D)  gamma rays 
E)  all of the above 
A)  infra-red radiation 
B)  radio waves 
C)  X-waves 
D)  gamma rays 
E)  all of the above

Question 10

A larger objective lens shows ____________ a smaller objective lens.

Accepted Answer

A)  more detail than 
B)  less detail than 
C)  the same amount of detail as 
A)  more detail than 
B)  less detail than 
C)  the same amount of detail as

Question 11

Astronomers build optical telescopes on tops of mountains because

Accepted Answer

A)  there is less air to dim the light. 
B)  the seeing is better. 
C)  CCDs work better when there is less oxygen in the air. 
D)  all of the above 
E)  a and b 
A)  there is less air to dim the light. 
B)  the seeing is better. 
C)  CCDs work better when there is less oxygen in the air. 
D)  all of the above 
E)  a and b

Question 12

A ____ is used to produce and analyze a spectrum.

Accepted Answer

A)  photo 
B)  spectrograph 
C)  photometer 
D)  charge-coupled device 
A)  photo 
B)  spectrograph 
C)  photometer 
D)  charge-coupled device

Question 13

The resolving power of a telescope is ____.

Accepted Answer

A)  a measure of the minimum angular separation between objects or details that can be seen with the telescope. 
B)  a measure of the maximum angular separation between objects or details that can be seen with the telescope. 
C)  a measure of the amount of light that the telescope can gather in one second. 
D)  the separation between the objective and the image. 
E)  a measure of how faint an object can be seen in the telescope. 
A)  a measure of the minimum angular separation between objects or details that can be seen with the telescope. 
B)  a measure of the maximum angular separation between objects or details that can be seen with the telescope. 
C)  a measure of the amount of light that the telescope can gather in one second. 
D)  the separation between the objective and the image. 
E)  a measure of how faint an object can be seen in the telescope.

Question 14

Observations of radio waves from astronomical objects suffer from poorer resolution than visible observations with the same size dish (or mirror)because

Accepted Answer

A)  the signals are so weak in the radio region. 
B)  the wavelength of radio waves is much longer than the wavelengths of visible light. 
C)  radio telescopes are generally much smaller in diameter than optical telescopes. 
D)  it is very difficult to detect radio waves. 
E)  radio telescopes don't use solid mirrors. 
A)  the signals are so weak in the radio region. 
B)  the wavelength of radio waves is much longer than the wavelengths of visible light. 
C)  radio telescopes are generally much smaller in diameter than optical telescopes. 
D)  it is very difficult to detect radio waves. 
E)  radio telescopes don't use solid mirrors.

Question 15

A ____ is a piece of glass or metal with many small parallel lines etched on its surface.

Accepted Answer

A)  grating 
B)  spectrograph 
C)  photometer 
D)  charge-coupled device 
E)  prism 
A)  grating 
B)  spectrograph 
C)  photometer 
D)  charge-coupled device 
E)  prism

Question 16

The largest optical telescope ever constructed was a refracting telescope.

Accepted Answer

A) True 
 B)False

Question 17

Light with a wavelength of 300 nm has a lower frequency than light with a wavelength of 500 nm.

Accepted Answer

A) True 
 B)False

Question 18

Violet light has a wavelength of approximately ____.

Accepted Answer

A)  400 nm 
B)  4000 nm 
C)  7000 nm 
D)  700 nm 
E)  3*108 m 
A)  400 nm 
B)  4000 nm 
C)  7000 nm 
D)  700 nm 
E)  3*108 m

Question 19

Radio telescopes with dishes are ____ telescopes.

Accepted Answer

A)  Reflecting 
B)  Refracting 
C)  Deflecting 
D)  Compound 
E)  Retracting 
A)  Reflecting 
B)  Refracting 
C)  Deflecting 
D)  Compound 
E)  Retracting

Question 20

The light-gathering power of a telescope is directly proportional to

Accepted Answer

A)  the area of the primary mirror or lens. 
B)  the focal length of the primary mirror or lens. 
C)  the ratio of the focal lengths of its primary mirror or lens and its eyepiece. 
D)  the length of the telescope tube. 
E)  the diameter of the eyepiece. 
A)  the area of the primary mirror or lens. 
B)  the focal length of the primary mirror or lens. 
C)  the ratio of the focal lengths of its primary mirror or lens and its eyepiece. 
D)  the length of the telescope tube. 
E)  the diameter of the eyepiece.

Exam 6: Light and Telescopes

Compared to a smaller objective lens,a larger objective lens makes a star's image ...

What statement below best describes the behavior of light encountering the objective lens of a refracting telescope?

An ordinary glass lens forms an image by ____________ of light.

Which has the larger light-gathering power?

Reflecting telescopes are no longer popular with astronomers because they are expensive and suffer from chromatic aberration.

The amount of energy a photon carries depends on its wavelength.

A(n)____________________ is used to measure the brightness and color of stars.

____ has (have)wavelengths that are shorter than visible light.

Infra-red space telescopes must have their mirror cooled to very low temperatures because otherwise it would thermally emit too much ____ itself.

A larger objective lens shows ____________ a smaller objective lens.

Astronomers build optical telescopes on tops of mountains because

A ____ is used to produce and analyze a spectrum.

The resolving power of a telescope is ____.

Observations of radio waves from astronomical objects suffer from poorer resolution than visible observations with the same size dish (or mirror)because

A ____ is a piece of glass or metal with many small parallel lines etched on its surface.

The largest optical telescope ever constructed was a refracting telescope.

Light with a wavelength of 300 nm has a lower frequency than light with a wavelength of 500 nm.

Violet light has a wavelength of approximately ____.

Radio telescopes with dishes are ____ telescopes.

The light-gathering power of a telescope is directly proportional to

Here and Now

A Users Guide to the Sky

Cycles of the Moon

The Origin of Modern Astronomy

Gravity

Atoms and Spectra

The Sun

The Family of Stars

The Interstellar Medium

The Formation and Structure of Stars

Stellar Evolution

The Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies

Active Galaxies and Supermassive Black Holes

Modern Cosmology

The Origin of the Solar System

Earth: the Standard of Comparative Planetology

The Moon and Mercury: Comparing Airless Worlds

Venus and Mars

Jupiter and Saturn

Uranus,neptune,and the Kuiper Belt

Meteorites,asteroids,and Comets

Astrobiology: Life on Other Worlds

Filters