Question 1

A black car left in the sunlight becomes hotter than a white car left in the sunlight under the same conditions because:

Accepted Answer

A) the white car absorbs more sunlight than the black car 
B) the white car reflects more sunlight than the black car 
C) the black car absorbs only blue photons and reflects red photons,whereas the white car absorbs only red photons and reflects blue photons 
D) the atoms in the black car are smaller than the atoms in the white car 
A) the white car absorbs more sunlight than the black car 
B) the white car reflects more sunlight than the black car 
C) the black car absorbs only blue photons and reflects red photons,whereas the white car absorbs only red photons and reflects blue photons 
D) the atoms in the black car are smaller than the atoms in the white car B

Question 2

In the quantum mechanical view of the atom,an electron is best thought of as:

Accepted Answer

A) a cloud that is centered on the nucleus 
B) a particle orbiting the nucleus 
C) free to orbit at any distance from the nucleus 
D) a particle inside the nucleus 
E) All of the above are true. 
A) a cloud that is centered on the nucleus 
B) a particle orbiting the nucleus 
C) free to orbit at any distance from the nucleus 
D) a particle inside the nucleus 
E) All of the above are true. A

Question 3

Why do some stars in the sky appear blue,while other stars appear red?

Accepted Answer

A) The red stars are hotter on their surfaces than the blue stars. 
B) The blue stars are hotter on their surfaces than the red stars. 
C) The blue stars are closer to us than the red stars. 
D) The red stars are closer to us than the blue stars. 
E) The blue stars are moving away from us faster than the red stars. 
A) The red stars are hotter on their surfaces than the blue stars. 
B) The blue stars are hotter on their surfaces than the red stars. 
C) The blue stars are closer to us than the red stars. 
D) The red stars are closer to us than the blue stars. 
E) The blue stars are moving away from us faster than the red stars. B

Question 4

The speed of light in a vacuum is:

Accepted Answer

A) 300,000 m/s 
B) 300,000 mph 
C) 300,000 km/s 
D) 300,000,000 mph 
E) infinite 
A) 300,000 m/s 
B) 300,000 mph 
C) 300,000 km/s 
D) 300,000,000 mph 
E) infinite

Question 5

Which of the following photons carry the smallest 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 m 
C) a red photon in the visible spectrum,whose wavelength is 700 nm 
D) a microwave photon,whose wavelength is 10−2 m 
E) an ultraviolet photon,whose wavelength is 300 nm 
A) a blue photon of the visible spectrum,whose wavelength is 450 nm 
B) an infrared photon,whose wavelength is 10−5 m 
C) a red photon in the visible spectrum,whose wavelength is 700 nm 
D) a microwave photon,whose wavelength is 10−2 m 
E) an ultraviolet photon,whose wavelength is 300 nm

Question 6

An emission line is produced when an atom absorbs a photon of a specific energy.

Accepted Answer

A) True 
 B)False

Question 7

Saying that something is quantized means that it:

Accepted Answer

A) is a wave 
B) is a particle 
C) travels at the speed of light 
D) can only have discrete quantities 
E) is smaller than an atom 
A) is a wave 
B) is a particle 
C) travels at the speed of light 
D) can only have discrete quantities 
E) is smaller than an atom

Question 8

A thin cloud of cool gas on top of a hotter blackbody will radiate an emission spectrum.

Accepted Answer

A) True 
 B)False

Question 9

The emission lines of a given atom occur at the exact same energies as that atom's absorption lines.

Accepted Answer

A) True 
 B)False

Question 10

If the Sun instantaneously stopped giving off light,what would happen on Earth?

Accepted Answer

A) It would immediately get dark. 
B) It would get dark 8 minutes later. 
C) It would get dark 27 minutes later. 
D) It would get dark 1 hour later. 
E) It would get dark 24 hours later. 
A) It would immediately get dark. 
B) It would get dark 8 minutes later. 
C) It would get dark 27 minutes later. 
D) It would get dark 1 hour later. 
E) It would get dark 24 hours later.

Question 11

The speed of light was first determined by which scientist?

Accepted Answer

A) Galileo 
B) Newton 
C) Kepler 
D) Rømer 
E) Einstein 
A) Galileo 
B) Newton 
C) Kepler 
D) Rømer 
E) Einstein

Question 12

If Saturn has a semimajor axis of 10 AU and an albedo of 0.7,what is its expected temperature?

Accepted Answer

A) 130 K 
B) 15 K 
C) 35 K 
D) 170 K 
E) 65 K 
A) 130 K 
B) 15 K 
C) 35 K 
D) 170 K 
E) 65 K

Question 13

For a star that lies in the plane of Earth's orbit around the Sun,how does the observed wavelength of the hydrogen absorption line at 656.28 nm in its spectrum change in wavelength (if at all)with the time of year?

Accepted Answer

The wavelength of this absorption line w

Question 14

Suppose you observe a star emitting a certain emission line of helium at 584.8 nm.The rest wavelength of this line is 587.6 nm.How fast is the star moving? Is it moving toward you or away from you?

Accepted Answer

The Doppler formula states that the radi

Question 15

Star A and star B appear equally bright in the sky.Star A is twice as far away from Earth as star B.How do the luminosities of stars A and B compare?

Accepted Answer

A) Star A is twice as luminous as star B. 
B) Star B is twice as luminous as star A. 
C) Star A is four times as luminous as star B. 
D) Star B is four times as luminous as star A. 
E) Stars A and B have the same luminosity. 
A) Star A is twice as luminous as star B. 
B) Star B is twice as luminous as star A. 
C) Star A is four times as luminous as star B. 
D) Star B is four times as luminous as star A. 
E) Stars A and B have the same luminosity.

Question 16

Astronomers have now found a large number of exoplanets,which are planets that orbit around stars other than the Sun.Imagine astronomers found a planet identical to the Earth orbiting a star that had the same radius as the Sun,but with a temperature that is twice the temperature of the Sun.How far would this new planet need to be away from its star to have the same average temperature as the Earth?

Accepted Answer

In order to have the same average temper

Question 17

Light with a wavelength of 600 nm has a frequency of:

Accepted Answer

A) 2 × 105 Hz 
B) 5 × 107 Hz 
C) 2 × 1010 Hz 
D) 5 × 1012 Hz 
E) 5 × 1014 Hz 
A) 2 × 105 Hz 
B) 5 × 107 Hz 
C) 2 × 1010 Hz 
D) 5 × 1012 Hz 
E) 5 × 1014 Hz

Question 18

If the wavelength of a beam of light were to double,how would that affect its frequency?

Accepted Answer

A) The frequency would be four times larger. 
B) The frequency would be two times larger. 
C) The frequency would be two times smaller 
D) The frequency would be four times smaller. 
E) There is no relationship between wavelength and frequency. 
A) The frequency would be four times larger. 
B) The frequency would be two times larger. 
C) The frequency would be two times smaller 
D) The frequency would be four times smaller. 
E) There is no relationship between wavelength and frequency.

Question 19

Your average body temperature is approximately 310 K,thus most of the light you radiate is at ultraviolet wavelengths.

Accepted Answer

A) True 
 B)False

Question 20

How can the average temperature of the Earth stay approximately constant,even though the Earth is always getting energy from the Sun?

Accepted Answer

The Earth is also giving off e

Exam 5: Light

A black car left in the sunlight becomes hotter than a white car left in the sunlight under the same conditions because:

In the quantum mechanical view of the atom,an electron is best thought of as:

Why do some stars in the sky appear blue,while other stars appear red?

The speed of light in a vacuum is:

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

An emission line is produced when an atom absorbs a photon of a specific energy.

Saying that something is quantized means that it:

A thin cloud of cool gas on top of a hotter blackbody will radiate an emission spectrum.

The emission lines of a given atom occur at the exact same energies as that atom's absorption lines.

If the Sun instantaneously stopped giving off light,what would happen on Earth?

The speed of light was first determined by which scientist?

If Saturn has a semimajor axis of 10 AU and an albedo of 0.7,what is its expected temperature?

For a star that lies in the plane of Earth's orbit around the Sun,how does the observed wavelength of the hydrogen absorption line at 656.28 nm in its spectrum change in wavelength (if at all)with the time of year?

Suppose you observe a star emitting a certain emission line of helium at 584.8 nm.The rest wavelength of this line is 587.6 nm.How fast is the star moving? Is it moving toward you or away from you?

Star A and star B appear equally bright in the sky.Star A is twice as far away from Earth as star B.How do the luminosities of stars A and B compare?

Light with a wavelength of 600 nm has a frequency of:

If the wavelength of a beam of light were to double,how would that affect its frequency?

Your average body temperature is approximately 310 K,thus most of the light you radiate is at ultraviolet wavelengths.

How can the average temperature of the Earth stay approximately constant,even though the Earth is always getting energy from the Sun?

Why Learn Astronomy

Patterns in the Skymotions of Earth

Motion of Astronomical Bodies

Gravity and Orbits

The Tools of the Astronomer

The Birth and Evolution of Planetary Systems

The Terrestrial Planets and Earths Moon

Atmospheres of the Terrestrial Planets

Worlds of Gas and Liquid the Giant Planets

Planetary Adornments Moons and Rings

Dwarf Planets and Small Solar System Bodies

Taking the Measure of Stars

Our Starthe Sun

Star Formation and the Interstellar Medium

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Relativity and Black Holes

The Expanding Universe

Galaxies

The Milky Waya Normal Spiral Galaxy

Modern Cosmology

Large-Scale Structure in the Universe

Life

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