Question 1

When an electron moves from a higher energy level in an atom to a lower energy level,

Accepted Answer

A)  the atom is ionized. 
B)  a continuous spectrum is emitted. 
C)  a photon is emitted. 
D)  a photon is absorbed. 
E)  the electron loses mass. 
A)  the atom is ionized. 
B)  a continuous spectrum is emitted. 
C)  a photon is emitted. 
D)  a photon is absorbed. 
E)  the electron loses mass.

Question 2

As an object's temperature increases, the atoms inside that object

Accepted Answer

A)  gain electrons. 
B)  increase in mass. 
C)  move at higher velocities. 
D)  emit less red light. 
E)  get larger. 
A)  gain electrons. 
B)  increase in mass. 
C)  move at higher velocities. 
D)  emit less red light. 
E)  get larger.

Question 3

The color of visible light is determined by its

Accepted Answer

A)  speed. 
B)  wavelength. 
C)  mass. 
D)  distance from you. 
E)  size. 
A)  speed. 
B)  wavelength. 
C)  mass. 
D)  distance from you. 
E)  size.

Question 4

In the quantum mechanical view of the atom, electrons are often depicted 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)  nothing, electrons are not part of an atom. 
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)  nothing, electrons are not part of an atom.

Question 5

Imagine you observed three different stars: a red star, a blue star, and a yellow star.You are able to determine that each of these stars has the same radius.Rank these stars according to surface temperature and overall luminosity, and explain your reasoning.

Accepted Answer

The blue star has the highest surface te

Question 6

A spaceship approaches Earth at 0.9 times the speed of light and shines a powerful searchlight onto Earth.How fast will the photons from this searchlight be moving when they hit Earth?

Accepted Answer

At the spe

Question 7

At what peak wavelength does your body radiate the most given that your temperature is approximately that of Earth, which is 300 K?

Accepted Answer

A)  10-5 m 
B)  10-3 m 
C)  10-2 m 
D)  10 m 
E)  1,000 m 
A)  10-5 m 
B)  10-3 m 
C)  10-2 m 
D)  10 m 
E)  1,000 m

Question 8

The wavelength of a wave is

Accepted Answer

A)  the total distance a wave travels 
B)  a measure of the wave's velocity. 
C)  the number of peaks that pass per second. 
D)  the maximum height of the wave above zero. 
E)  the distance between one peak value and the next peak. 
A)  the total distance a wave travels 
B)  a measure of the wave's velocity. 
C)  the number of peaks that pass per second. 
D)  the maximum height of the wave above zero. 
E)  the distance between one peak value and the next peak.

Question 9

Explain what is meant when someone refers to "thermal motions."

Accepted Answer

Temperature can be related to the averag

Question 10

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 11

In the figure below, which blackbody spectrum corresponds to the object that would appear the reddest to the human eye?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 12

Which of these stars would have the biggest redshift?

Accepted Answer

A)  a star moving at low speed toward you 
B)  a star moving at high speed toward you 
C)  a star moving at low speed away from you 
D)  a star moving at high speed away from you 
E)  a star that is not moving away from you or toward you 
A)  a star moving at low speed toward you 
B)  a star moving at high speed toward you 
C)  a star moving at low speed away from you 
D)  a star moving at high speed away from you 
E)  a star that is not moving away from you or toward you

Question 13

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 14

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

As Earth moves toward the star

Question 15

Imagine a satellite is orbiting a planet other than Earth.This satellite gives off radio waves with a constant wavelength of 1 m.An observer on Earth then measures the signal from the satellite when it is directly between Earth and the planet.How does the wavelength received compare to the wavelength that the satellite gave off?

Accepted Answer

The received signal will be ex

Question 16

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)  ultraviolet photons have less energy than visible photons. 
E)  all photons have the same wavelength. 
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)  ultraviolet photons have less energy than visible photons. 
E)  all photons have the same wavelength.

Question 17

What is an electromagnetic wave?

Accepted Answer

Unlike a wave on water,which requires wa

Question 18

A nanometer is ________ of a meter.

Accepted Answer

A)  1/100 
B)  1/1,000 
C)  1/1,000,000 
D)  1/1,000,000,000 
E)  1/1,000,000,000,000 
A)  1/100 
B)  1/1,000 
C)  1/1,000,000 
D)  1/1,000,000,000 
E)  1/1,000,000,000,000

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. 
E)  Light can't travel through a medium; it only can go through a vacuum. 
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. 
E)  Light can't travel through a medium; it only can go through a vacuum.

Question 20

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

Exam 5: Light

When an electron moves from a higher energy level in an atom to a lower energy level,

As an object's temperature increases, the atoms inside that object

The color of visible light is determined by its

In the quantum mechanical view of the atom, electrons are often depicted as

Imagine you observed three different stars: a red star, a blue star, and a yellow star.You are able to determine that each of these stars has the same radius.Rank these stars according to surface temperature and overall luminosity, and explain your reasoning.

A spaceship approaches Earth at 0.9 times the speed of light and shines a powerful searchlight onto Earth.How fast will the photons from this searchlight be moving when they hit Earth?

At what peak wavelength does your body radiate the most given that your temperature is approximately that of Earth, which is 300 K?

The wavelength of a wave is

Explain what is meant when someone refers to "thermal motions."

The speed of light in a vacuum is

In the figure below, which blackbody spectrum corresponds to the object that would appear the reddest to the human eye?

Which of these stars would have the biggest redshift?

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?

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?

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

What is an electromagnetic wave?

A nanometer is ________ of a meter.

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

Light with a wavelength of 600 nm has a frequency of

Thinking Like an Astronomer

Patterns in the Skymotions of Earth and the Moon

Motion of Astronomical Bodies

Gravity and Orbits

The Tools of the Astronomer

The Formation of Planetary Systems

The Terrestrial Planets and Earths Moon

Atmospheres of the Terrestrial Planets

Worlds of Gas and Liquidthe Giant Planets

Planetary Moons and Rings

Dwarf Planets and Small Solar System Bodies

Taking the Measure of Stars

Our Starthe Sun

The Interstellar Medium and Star Formation

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Relativity and Black Holes

Galaxies

The Milky Waya Normal Spiral Galaxy

The Expanding Universe

Cosmology

Large-Scale Structure in the Universe

Life

Filters