Question 1

Using Wien's law, what is the approximate peak wavelength of radiation emitted by (live) human beings, who are (normally) at a temperature of about 310 K (1 μm = 10-6 m)?

Accepted Answer

A) 9.4 μm 
B) 3.1 μm 
C) 94 μm 
D) 0.94 μm 
A) 9.4 μm 
B) 3.1 μm 
C) 94 μm 
D) 0.94 μm A

Question 2

A police radar bounces microwaves of wavelength 3 mm from the front of a speeding car and measures the Doppler shift in wavelength of the reflected waves. The shift is doubled because of the reflection. What will be the wavelength shift if the speeding car is moving at 60 mph (80 km/h or 22.2 ms-1)?

Accepted Answer

A) 0.44 nm 
B) 0.88 nm 
C) 4.4 nm 
D) 8.8 nm 
A) 0.44 nm 
B) 0.88 nm 
C) 4.4 nm 
D) 8.8 nm A

Question 3

You are looking at a glowing field of hot lava from a satellite high above Earth's atmosphere. Hot lava emits most of its radiation in the infrared, and Earth's atmosphere is not completely transparent to infrared. What kind of spectrum will you see?

Accepted Answer

A) a flat spectrum, equally intense at short and long wavelengths 
B) an emission spectrum 
C) an absorption spectrum 
D) no spectrum at any wavelength 
A) a flat spectrum, equally intense at short and long wavelengths 
B) an emission spectrum 
C) an absorption spectrum 
D) no spectrum at any wavelength C

Question 4

The upward Lyman series transitions in hydrogen begin with electrons in the ground state (n = 1), which is the state of most hydrogen atoms. Yet the Balmer series was studied first and was the basis of the early attempts to explain the lines. This is because:

Accepted Answer

A) upward transitions never occur; only downward transitions occur. 
B) the entire Balmer series is in the visible part of the spectrum. 
C) the first few transitions (low n) in the Balmer series are in the visible. 
D) the last few transitions (high n) in the Balmer series are in the visible. 
A) upward transitions never occur; only downward transitions occur. 
B) the entire Balmer series is in the visible part of the spectrum. 
C) the first few transitions (low n) in the Balmer series are in the visible. 
D) the last few transitions (high n) in the Balmer series are in the visible.

Question 5

What happens in general when ultraviolet radiation passes through a tube of cool hydrogen gas?

Accepted Answer

A) Radiation at all wavelengths is absorbed, reducing the intensity at all wavelengths uniformly. 
B) It is unhindered except at the specific wavelengths of the Lyman series, L $\alpha$ , Lß, etc, which are absorbed by the atoms. 
C) It is unhindered except the Lyman L $\alpha$ wavelength, which is absorbed by the atoms. 
D) It is unhindered since the hydrogen gas is cool and cannot absorb energy. 
A) Radiation at all wavelengths is absorbed, reducing the intensity at all wavelengths uniformly. 
B) It is unhindered except at the specific wavelengths of the Lyman series, L $\alpha$ , Lß, etc, which are absorbed by the atoms. 
C) It is unhindered except the Lyman L $\alpha$ wavelength, which is absorbed by the atoms. 
D) It is unhindered since the hydrogen gas is cool and cannot absorb energy.

Question 6

How do the spectra of the two isotopes 1H and 2H compare?

Accepted Answer

A) These isotopes each have one proton, which makes them both hydrogen, so they have identical spectra. 
B) The wavelengths for the heavier isotope are very slightly longer than those for the lighter isotope. 
C) The wavelengths for the heavier isotope are very slightly shorter than those for the lighter isotope. 
D) Since the nuclei are different, the two spectra differ greatly. 
A) These isotopes each have one proton, which makes them both hydrogen, so they have identical spectra. 
B) The wavelengths for the heavier isotope are very slightly longer than those for the lighter isotope. 
C) The wavelengths for the heavier isotope are very slightly shorter than those for the lighter isotope. 
D) Since the nuclei are different, the two spectra differ greatly.

Question 7

According to the arrangement of elements in the periodic table, which of the following elements would be expected to have chemical properties most similar to those of nitrogen, N, whose atomic number is 7?
​
  ​

Accepted Answer

A) oxygen (O, atomic number 8) 
B) phosphorous (P, atomic number 15) 
C) chlorine (Cl, atomic number 17) 
D) carbon (C, atomic number 6) 
A) oxygen (O, atomic number 8) 
B) phosphorous (P, atomic number 15) 
C) chlorine (Cl, atomic number 17) 
D) carbon (C, atomic number 6)

Question 8

The energy E of a photon or quantum of electromagnetic radiation is related to the wavelength λ of the radiation by what relation (h = Planck's constant)?

Accepted Answer

A) E = hc/λ 
B) E = hλ 
C) E = hcλ 
D) E = h/cλ 
A) E = hc/λ 
B) E = hλ 
C) E = hcλ 
D) E = h/cλ

Question 9

The overall diameter of a typical atom is about:

Accepted Answer

A) 10-7 m, or 102 nm. 
B) 10-5 m, or 104 nm. 
C) 10-14 m, or 10-5 nm. 
D) 10-10 m, or 0.1 nm. 
A) 10-7 m, or 102 nm. 
B) 10-5 m, or 104 nm. 
C) 10-14 m, or 10-5 nm. 
D) 10-10 m, or 0.1 nm.

Question 10

What type of radiation is emitted by hot hydrogen gas when electrons jump from the n = 8 level to the n = 7 level of the atoms?

Accepted Answer

A) 52,489 m, in the radio 
B) 1.905 μm, in the near infrared 
C) 19.05 μm, in the infrared 
D) 38.9 nm, in the ultraviolet 
A) 52,489 m, in the radio 
B) 1.905 μm, in the near infrared 
C) 19.05 μm, in the infrared 
D) 38.9 nm, in the ultraviolet

Question 11

What is the wavelength of radio waves from the FM radio station KTYD, which operates at the frequency 99.9 MHz?

Accepted Answer

A) 99.9 m 
B) 3.0 m 
C) 300 m 
D) 33.3 m 
A) 99.9 m 
B) 3.0 m 
C) 300 m 
D) 33.3 m

Question 12

No matter how close or how far Galileo was from his assistant, he always measured roughly the same time in performing the lantern experiment. Just what time was Galileo measuring?

Accepted Answer

A) the time for light to travel from his assistant to himself 
B) the round-trip time for light to travel between Galileo and his assistant 
C) his own reaction time-that is, the time for him to open his shutter after observing his assistant's light 
D) the combined reaction time of Galileo and his assistant 
A) the time for light to travel from his assistant to himself 
B) the round-trip time for light to travel between Galileo and his assistant 
C) his own reaction time-that is, the time for him to open his shutter after observing his assistant's light 
D) the combined reaction time of Galileo and his assistant

Question 13

In its interaction with matter, light behaves:

Accepted Answer

A) only as waves. 
B) alternatively as particles or as waves, switching its properties about once every second. 
C) as both waves and particles, depending on the type of interaction. 
D) only as small particles, photons. 
A) only as waves. 
B) alternatively as particles or as waves, switching its properties about once every second. 
C) as both waves and particles, depending on the type of interaction. 
D) only as small particles, photons.

Question 14

Using Wien's law, which relates the peak wavelength λmax, (1 μm = 10-6 m) emitted by a body to its temperature T, what is the peak wavelength of electromagnetic radiation emitted by a piece of iron that is just melting (1538°C)? (See Box 5-2 and Figure 5-7 of Universe, 11th ed.)

Accepted Answer

A) 16 μm, intermediate infrared 
B) 1.89 μm, near infrared 
C) 1.04 μm, very near infrared 
D) 1.6 μm, near infrared 
A) 16 μm, intermediate infrared 
B) 1.89 μm, near infrared 
C) 1.04 μm, very near infrared 
D) 1.6 μm, near infrared

Question 15

What is the wavelength of electromagnetic radiation whose frequency is 106 cycles per second (106 Hz or 1000 kHz, the frequency of ordinary AM radio)?

Accepted Answer

A) 3 mm 
B) 3 cm 
C) 3 m 
D) 300 m 
A) 3 mm 
B) 3 cm 
C) 3 m 
D) 300 m

Question 16

The dark absorption lines in the solar spectrum are caused by absorption:

Accepted Answer

A) of sunlight in a layer of pure hydrogen gas overlying the solar surface. 
B) of sunlight in a cooler layer of gas overlying the hot solar surface. 
C) entirely by atoms and molecules in Earth's cool atmosphere. 
D) of sunlight in a hotter layer of gas overlying the cooler solar surface. 
A) of sunlight in a layer of pure hydrogen gas overlying the solar surface. 
B) of sunlight in a cooler layer of gas overlying the hot solar surface. 
C) entirely by atoms and molecules in Earth's cool atmosphere. 
D) of sunlight in a hotter layer of gas overlying the cooler solar surface.

Question 17

Which one of these scientists was the last to perform his investigation of electromagnetic radiation?

Accepted Answer

A) Newton (the prism experiment) 
B) Hertz (production of radio waves) 
C) Young (two-slit interference experiment) 
D) Huygens (wave theory of light) 
A) Newton (the prism experiment) 
B) Hertz (production of radio waves) 
C) Young (two-slit interference experiment) 
D) Huygens (wave theory of light)

Question 18

Around 1801, Thomas Young in England showed that light behaves as a wave by:

Accepted Answer

A) deriving a set of mathematical equations that described electromagnetic waves that could have different wavelengths. 
B) shining light through two closely spaced slits and observing the resulting pattern of light on a white screen. 
C) reflecting light from a rotating mirror and measuring the deflection in different directions. 
D) shining light through a glass prism and observing the resulting pattern of colors on a white screen. 
A) deriving a set of mathematical equations that described electromagnetic waves that could have different wavelengths. 
B) shining light through two closely spaced slits and observing the resulting pattern of light on a white screen. 
C) reflecting light from a rotating mirror and measuring the deflection in different directions. 
D) shining light through a glass prism and observing the resulting pattern of colors on a white screen.

Question 19

Proxima Centauri, our Sun's nearest stellar neighbor, has a surface temperature of about 3300 K. What color will this star appear to the naked eye?

Accepted Answer

A) red 
B) yellow 
C) white 
D) blue 
A) red 
B) yellow 
C) white 
D) blue

Question 20

The Sun's surface has a temperature of 5800 K. What will be the peak wavelength of the spectrum of a star that emits twice the Sun's flux of energy?

Accepted Answer

A) 2.1 × 10-7 m 
B) 4.0 × 10-7 m 
C) 5.0 × 10-7 m 
D) 1.0 × 10-6 m 
A) 2.1 × 10-7 m 
B) 4.0 × 10-7 m 
C) 5.0 × 10-7 m 
D) 1.0 × 10-6 m

Exam 5: The Nature of Light

Using Wien's law, what is the approximate peak wavelength of radiation emitted by (live) human beings, who are (normally) at a temperature of about 310 K (1 μm = 10-6 m)?

You are looking at a glowing field of hot lava from a satellite high above Earth's atmosphere. Hot lava emits most of its radiation in the infrared, and Earth's atmosphere is not completely transparent to infrared. What kind of spectrum will you see?

The upward Lyman series transitions in hydrogen begin with electrons in the ground state (n = 1), which is the state of most hydrogen atoms. Yet the Balmer series was studied first and was the basis of the early attempts to explain the lines. This is because:

What happens in general when ultraviolet radiation passes through a tube of cool hydrogen gas?

How do the spectra of the two isotopes 1H and 2H compare?

According to the arrangement of elements in the periodic table, which of the following elements would be expected to have chemical properties most similar to those of nitrogen, N, whose atomic number is 7? ​ ​

The energy E of a photon or quantum of electromagnetic radiation is related to the wavelength λ of the radiation by what relation (h = Planck's constant)?

The overall diameter of a typical atom is about:

What type of radiation is emitted by hot hydrogen gas when electrons jump from the n = 8 level to the n = 7 level of the atoms?

What is the wavelength of radio waves from the FM radio station KTYD, which operates at the frequency 99.9 MHz?

No matter how close or how far Galileo was from his assistant, he always measured roughly the same time in performing the lantern experiment. Just what time was Galileo measuring?

In its interaction with matter, light behaves:

Using Wien's law, which relates the peak wavelength λmax, (1 μm = 10-6 m) emitted by a body to its temperature T, what is the peak wavelength of electromagnetic radiation emitted by a piece of iron that is just melting (1538°C)? (See Box 5-2 and Figure 5-7 of Universe, 11th ed.)

What is the wavelength of electromagnetic radiation whose frequency is 106 cycles per second (106 Hz or 1000 kHz, the frequency of ordinary AM radio)?

The dark absorption lines in the solar spectrum are caused by absorption:

Which one of these scientists was the last to perform his investigation of electromagnetic radiation?

Around 1801, Thomas Young in England showed that light behaves as a wave by:

Proxima Centauri, our Sun's nearest stellar neighbor, has a surface temperature of about 3300 K. What color will this star appear to the naked eye?

The Sun's surface has a temperature of 5800 K. What will be the peak wavelength of the spectrum of a star that emits twice the Sun's flux of energy?

Astronomy and the Universe

Knowing the Heavens

Eclipses and the Motion of the Moon

Gravitation and the Waltz of the Planets

Optics and Telescopes

Comparative Planetology I: Our Solar System

Comparative Planetology II: the Origin of Our Solar System

The Living Earth

Our Barren Moon

Mercury, Venus, and Mars: Terrestrial, yet Unique

Jupiter and Saturn: Lords of the Planets

Jupiter and Saturns Satellites of Fire and Ice

Uranus, Neptune, Pluto, and the Kuiper Belt: Remote Worlds

Asteroids, Comets, and Impacts

Our Star, the Sun

The Nature of the Stars

The Birth of Stars

Stellar Evolution: on and After the Main Sequence

Stellar Evolution: The Death of Stars

Stellar Remnants: Neutron Stars and Black Holes

Our Galaxy

Galaxies

Quasars and Active Galaxies

Cosmology: The Origin and Evolution of the Universe

Exploring the Early Universe

The Search for Extraterrestrial Life

Filters

Using Wien's law, what is the approximate peak wavelength of radiation emitted by (live) human beings, who are (normally) at a temperature of about 310 K (1 μm = 10^-6 m)?

How do the spectra of the two isotopes ¹H and ²H compare?

According to the arrangement of elements in the periodic table, which of the following elements would be expected to have chemical properties most similar to those of nitrogen, N, whose atomic number is 7?

Using Wien's law, which relates the peak wavelength λ_max, (1 μm = 10^-6 m) emitted by a body to its temperature T, what is the peak wavelength of electromagnetic radiation emitted by a piece of iron that is just melting (1538°C)? (See Box 5-2 and Figure 5-7 of Universe, 11th ed.)

What is the wavelength of electromagnetic radiation whose frequency is 10⁶ cycles per second (10⁶ Hz or 1000 kHz, the frequency of ordinary AM radio)?