Question 1

Which type of electromagnetic radiation travels fastest in a vacuum?

Accepted Answer

A) radio 
B) visible light 
C) X-ray 
D) gamma rays 
E) They all travel at the same speed. 
A) radio 
B) visible light 
C) X-ray 
D) gamma rays 
E) They all travel at the same speed.

Question 2

The hottest objects, with temperatures in the millions of Kelvins, give off most of theirradiation in which part of the electromagnetic spectrum?

Accepted Answer

A) visible 
B) radio 
C) ultraviolet 
D) X-ray 
E) gamma ray 
A) visible 
B) radio 
C) ultraviolet 
D) X-ray 
E) gamma ray

Question 3

Consider this diagram. Which statement is true?

Accepted Answer

A) The amplitude is 4. 
B) The amplitude is 6. 
C) The amplitude is 8. 
D) The amplitude is 12. 
E) The amplitude cannot be determined from this diagram. 
A) The amplitude is 4. 
B) The amplitude is 6. 
C) The amplitude is 8. 
D) The amplitude is 12. 
E) The amplitude cannot be determined from this diagram.

Question 4

Which statement gives the relationship between the waves in the electric and magnetic fieldsin an electromagnetic wave?

Accepted Answer

A) They are in phase and parallel with each other in space. 
B) They are 90 degrees out of phase but parallel in space. 
C) They are in phase but perpendicular to each other in space. 
D) They are 180 degrees out of phase and random in their inclinations to each other. 
E) They are in phase but opposite in direction of motion. 
A) They are in phase and parallel with each other in space. 
B) They are 90 degrees out of phase but parallel in space. 
C) They are in phase but perpendicular to each other in space. 
D) They are 180 degrees out of phase and random in their inclinations to each other. 
E) They are in phase but opposite in direction of motion.

Question 5

Star A and star B have the same temperature, but star B is more luminous than star A. Whatcan you infer about these two stars?

Accepted Answer

A) Star A must be bigger. 
B) Star B must be bigger. 
C) Star A must be redder. 
D) Star B must be redder. 
E) Nothing can be inferred from the information given. 
A) Star A must be bigger. 
B) Star B must be bigger. 
C) Star A must be redder. 
D) Star B must be redder. 
E) Nothing can be inferred from the information given.

Question 6

A blue star has a higher surface temperature than a red star.

Accepted Answer

A) True 
 B)False

Question 7

There are no X-ray telescopes on Earth because:

Accepted Answer

A) they are too expensive to build. 
B) no one has yet invented an X-ray telescope that works. 
C) we can't figure out how to direct an X-ray beam through space. 
D) X-rays don't penetrate Earth's atmosphere. 
E) there are no astronomical objects that emit X-rays. 
A) they are too expensive to build. 
B) no one has yet invented an X-ray telescope that works. 
C) we can't figure out how to direct an X-ray beam through space. 
D) X-rays don't penetrate Earth's atmosphere. 
E) there are no astronomical objects that emit X-rays.

Question 8

What is meant by the wavelength of light? By its frequency? Show how they are related toeach other.

Accepted Answer

The wavelength is the distance between s

Question 9

Star A and star B have the same temperature, but different luminosities. What can you inferabout these two stars?

Accepted Answer

A) Star A must be bigger. 
B) Star B must be bigger. 
C) Star A must be redder. 
D) Star B must be redder. 
E) Nothing can be inferred from the information given. 
A) Star A must be bigger. 
B) Star B must be bigger. 
C) Star A must be redder. 
D) Star B must be redder. 
E) Nothing can be inferred from the information given.

Question 10

Increasing the temperature of a blackbody by a factor of 3 will increase its energy by a factorof:

Accepted Answer

A) 3. 
B) 6. 
C) 9. 
D) 12. 
E) 81. 
A) 3. 
B) 6. 
C) 9. 
D) 12. 
E) 81.

Question 11

A   dim, young star like He rbig-Haro 68 emits most of its light in which part of theelectromagnetic spectrum?

Accepted Answer

A) the visible 
B) the X-ray 
C) the ultraviolet 
D) the radio 
E) the infrared 
A) the visible 
B) the X-ray 
C) the ultraviolet 
D) the radio 
E) the infrared

Question 12

Use Wien's Law to determine the peak wavelength of a star whose temperature is 10,000 K(similar temperature to the star Sirius). What color is this? Explain.

Accepted Answer

Wien's Law says that the peak wavelength

Question 13

What does the phenomenon of interference demonstrate?

Accepted Answer

A) the wave nature of light 
B) the polarization of light waves 
C) the quantization of the atomic orbitals 
D) the particle nature of the photon 
E) the process of ionization 
A) the wave nature of light 
B) the polarization of light waves 
C) the quantization of the atomic orbitals 
D) the particle nature of the photon 
E) the process of ionization

Question 14

If a beam of blue light with a wavelength of 400 nm is emitted by an object moving awayfrom you at $1 \%$ o the speed of light, what wavelength would you see from this light?

Accepted Answer

A) 396 nm 
B) 399 nm 
C) 400 nm 
D) 401 nm 
E) 404 nm 
A) 396 nm 
B) 399 nm 
C) 400 nm 
D) 401 nm 
E) 404 nm

Question 15

The distance from a wave's crest to its undisturbed state is the ________.

Accepted Answer

The answer of The distance from a wave's crest to...

Question 16

What does the phenomenon of diffraction demonstrate?

Accepted Answer

A) the wave nature of light 
B) the polarization of light waves 
C) the quantization of atomic orbitals 
D) the particle nature of the photon 
E) the process of ionization 
A) the wave nature of light 
B) the polarization of light waves 
C) the quantization of atomic orbitals 
D) the particle nature of the photon 
E) the process of ionization

Question 17

According to Wien's law, the higher the surface temperature of a star, the redder its color.

Accepted Answer

A) True 
 B)False

Question 18

What are the similarities and differences between the Kelvin and Fahrenheit temperaturescales? Identify the freezing point of water on both scales.

Accepted Answer

The Fahrenheit scale is an archaic scale

Question 19

Contrast the speeds of sound and light in watching a flash of lightning, then listening for thethunder to follow.

Accepted Answer

Light travels at 300,000 km/sec, so the

Question 20

How do Stefan's law and a knowledge of Earth's history tell us that the Sun's temperaturecannot have varied much in the last 3.5 billion years?

Accepted Answer

Since even a small change in temperature

Exam 3: Radiation: Information From the Cosmos

Which type of electromagnetic radiation travels fastest in a vacuum?

The hottest objects, with temperatures in the millions of Kelvins, give off most of theirradiation in which part of the electromagnetic spectrum?

Consider this diagram. Which statement is true?

Which statement gives the relationship between the waves in the electric and magnetic fieldsin an electromagnetic wave?

Star A and star B have the same temperature, but star B is more luminous than star A. Whatcan you infer about these two stars?

A blue star has a higher surface temperature than a red star.

There are no X-ray telescopes on Earth because:

What is meant by the wavelength of light? By its frequency? Show how they are related toeach other.

Star A and star B have the same temperature, but different luminosities. What can you inferabout these two stars?

Increasing the temperature of a blackbody by a factor of 3 will increase its energy by a factorof:

A dim, young star like He rbig-Haro 68 emits most of its light in which part of theelectromagnetic spectrum?

Use Wien's Law to determine the peak wavelength of a star whose temperature is 10,000 K(similar temperature to the star Sirius). What color is this? Explain.

What does the phenomenon of interference demonstrate?

If a beam of blue light with a wavelength of 400 nm is emitted by an object moving awayfrom you at 1%1 \%1% o the speed of light, what wavelength would you see from this light?

The distance from a wave's crest to its undisturbed state is the ________.

What does the phenomenon of diffraction demonstrate?

According to Wien's law, the higher the surface temperature of a star, the redder its color.

What are the similarities and differences between the Kelvin and Fahrenheit temperaturescales? Identify the freezing point of water on both scales.

Contrast the speeds of sound and light in watching a flash of lightning, then listening for thethunder to follow.

How do Stefan's law and a knowledge of Earth's history tell us that the Sun's temperaturecannot have varied much in the last 3.5 billion years?

Charting the Heavens: The Foundations of Astronomy

The Copernican Revolution: The Birth of Modern Science

Spectroscopy: the Inner Workings of Atoms

Telescopes: The Tools of Astronomy

The Solar System: Comparative Planetology and Formation Models

Earth: Our Home in Space

The Moon and Mercury: Scorched and Battered Worlds

Venus: Earths Sister Planet

Mars: a Near Miss for Life

Jupiter: Giant of the Solar System

Saturn: Spectacular Rings and Mysterious Moons

Uranus and Neptune: The Outer Worlds of the Solar System

Solar System Debris: Keys to Our Origin

Exoplanets: Planetary Systems Beyond Our Own

The Sun: Our Parent Star

The Stars: Giants, Dwarfs, and the Main Sequence

The Interstellar Medium: Gas and Dust Among the Stars

Star Formation: a Traumatic Birth

Stellar Evolution: The Life and Death of a Star

Stellar Explosions: Novae, Supernovae, and the Formation of the Elements

Neutron Stars and Black Holes: Strange States of Matter

The Milky Way Galaxy: a Spiral in Space

Galaxies: Building Blocks of the Universe

Galaxies and Dark Matter: The Large-Scale Structure of the Cosmos

Cosmology: The Big Bang and the Fate of the Universe

The Early Universe: Toward the Beginning of Time

Life in the Universe: Are We Alone

Filters

If a beam of blue light with a wavelength of 400 nm is emitted by an object moving awayfrom you at $1 \%$ o the speed of light, what wavelength would you see from this light?