Question 1

Where does the Paschen series of spectral lines from hydrogen gas appear in the electromagnetic spectrum?

Accepted Answer

A)  radio range, with wavelengths longer than 0.01 m or 10 mm 
B)  ultraviolet region, with wavelengths between 90 nm and 130 nm 
C)  infrared, with wavelengths longer than 700 nm 
D)  visible region, with wavelengths between 350 nm to 660 nm 
A)  radio range, with wavelengths longer than 0.01 m or 10 mm 
B)  ultraviolet region, with wavelengths between 90 nm and 130 nm 
C)  infrared, with wavelengths longer than 700 nm 
D)  visible region, with wavelengths between 350 nm to 660 nm

Question 2

The Stefan-Boltzmann law, which relates the energy per unit area F emitted by an object to its temperature T, F = $\sigma$T4, is obeyed by what kind of object?

Accepted Answer

A)  red-colored object, which absorbs blue light but reflects red light 
B)  only hot gases, whose atoms emit and absorb only specific colors (e.g., neon tubes) 
C)  blackbody, a perfect absorber and emitter of energy at all wavelengths 
D)  all objects, whatever their color or reflective properties 
A)  red-colored object, which absorbs blue light but reflects red light 
B)  only hot gases, whose atoms emit and absorb only specific colors (e.g., neon tubes) 
C)  blackbody, a perfect absorber and emitter of energy at all wavelengths 
D)  all objects, whatever their color or reflective properties

Question 3

If a continuous spectrum of ultraviolet radiation passes through a tube of cool hydrogen gas, what happens to its spectrum?

Accepted Answer

A)  All the radiation passes unhindered except the Lyman L $\alpha$ wavelength, which is absorbed by the atoms. 
B)  Some of the radiation at all wavelengths is absorbed, reducing the intensity at all wavelengths uniformly. 
C)  All the radiation passes through the tube unhindered because the hydrogen gas is cool and cannot absorb energy. 
D)  All the radiation passes through the tube unhindered except at the specific wavelengths of the Lyman series, L $\alpha$ , L $\beta$ , and so on, which are absorbed by the atoms. 
A)  All the radiation passes unhindered except the Lyman L $\alpha$ wavelength, which is absorbed by the atoms. 
B)  Some of the radiation at all wavelengths is absorbed, reducing the intensity at all wavelengths uniformly. 
C)  All the radiation passes through the tube unhindered because the hydrogen gas is cool and cannot absorb energy. 
D)  All the radiation passes through the tube unhindered except at the specific wavelengths of the Lyman series, L $\alpha$ , L $\beta$ , and so on, which are absorbed by the atoms.

Question 4

In his scattering experiment, Ernest Rutherford expected that the alpha particles he was using as bullets would easily penetrate his gold foil target with no backscatter. What was the actual result of the experiment?

Accepted Answer

A)  It was as expected-no backscattered alpha particles. 
B)  Surprisingly, all of the alpha particles were scattered back from the foil without penetrating. 
C)  About half of the alpha particles were backscattered. 
D)  Almost all of the alpha particles penetrated the foil, but a few were backscattered into the direction from which they had come. 
A)  It was as expected-no backscattered alpha particles. 
B)  Surprisingly, all of the alpha particles were scattered back from the foil without penetrating. 
C)  About half of the alpha particles were backscattered. 
D)  Almost all of the alpha particles penetrated the foil, but a few were backscattered into the direction from which they had come.

Question 5

Figure 4-2 in the text shows that a blackbody with a temperature of 3000 K emits radiation that peaks at a wavelength much longer than wavelengths in the visible part of the spectrum. This means that the object

Accepted Answer

A)  is not visible but might be detected with equipment sensitive to nonvisible radiation. 
B)  emits no radiation, like all blackbodies. 
C)  emits visible radiation but not as intensely as at longer wavelengths. 
D)  emits no visible radiation but would emit visible radiation if its temperature were increased. 
A)  is not visible but might be detected with equipment sensitive to nonvisible radiation. 
B)  emits no radiation, like all blackbodies. 
C)  emits visible radiation but not as intensely as at longer wavelengths. 
D)  emits no visible radiation but would emit visible radiation if its temperature were increased.

Question 6

The normal temperature of the melting point of water ice is

Accepted Answer

A)  293 K. 
B)  273 K. 
C)  0 K. 
D)  100 K. 
A)  293 K. 
B)  273 K. 
C)  0 K. 
D)  100 K.

Question 7

The amount of radiation emitted by a blackbody depends on all of these properties of the blackbody EXCEPT

Accepted Answer

A)  the wavelength under consideration. 
B)  the temperature. 
C)  the chemical composition. 
D)  the surface area. 
A)  the wavelength under consideration. 
B)  the temperature. 
C)  the chemical composition. 
D)  the surface area.

Question 8

Which of these equations represents the dependence of the total energy flux F of radiation emitted per unit area by a blackbody (e.g., star) on its temperature T with $\sigma$ a constant?

Accepted Answer

A)  FT4 = $\sigma$ 
B)  F4 = $\sigma$T 
C)  F =$\sigma$/T 
D)  F = $\sigma$T4 
A)  FT4 = $\sigma$ 
B)  F4 = $\sigma$T 
C)  F =$\sigma$/T 
D)  F = $\sigma$T4

Question 9

A police radar device bounces radio waves of wavelength 3 mm from the front of a speeding car and measures the Doppler shift in wavelength of the reflected waves. What will be the wavelength shift if the car is moving at 60 mph (80 km/h or 22.2 m/s) (in a 30 mph zone)? Note that the shift is doubled because of the reflection.

Accepted Answer

A)  0.44 nm 
B)  0.44 $\mu$m 
C)  4.4 $\mu$m 
D)  4.4 m 
A)  0.44 nm 
B)  0.44 $\mu$m 
C)  4.4 $\mu$m 
D)  4.4 m

Question 10

Huge fluxes of X-rays are detected from the direction of Cygnus X-1 with a spectrum that looks similar to that of a blackbody with a peak wavelength of 1.45 nm (1 nm = 10-9 m). These X-rays are probably emitted by matter being heated as it falls into a black hole. What is the temperature of this gas?

Accepted Answer

A)  2 * 106 K 
B)  4205 K 
C)  2 * 10-2 K 
D)  2* 104 K 
A)  2 * 106 K 
B)  4205 K 
C)  2 * 10-2 K 
D)  2* 104 K

Question 11

The proton, the nucleus of the hydrogen atom, has a mass that exceeds that of the electron by approximately what factor?

Accepted Answer

A)  2000 times 
B)  2 times 
C)  100 times 
D)  104 times 
A)  2000 times 
B)  2 times 
C)  100 times 
D)  104 times

Question 12

A piece of iron is heated from 400 K to 800 K. The total energy emitted per second by this iron will increase by a factor of

Accepted Answer

A)  296.5. 
B)  4. 
C)  2. 
D)  16. 
A)  296.5. 
B)  4. 
C)  2. 
D)  16.

Question 13

One problem with using a glass prism to produce a spectrum from white light is that

Accepted Answer

A)  glass absorbs almost all of the infrared in the white light. 
B)  glass absorbs almost all of the ultraviolet in the white light. 
C)  blue and violet do not spread out very much as a result of passing through the prism. 
D)  red is absorbed more than is the rest of the spectrum. 
A)  glass absorbs almost all of the infrared in the white light. 
B)  glass absorbs almost all of the ultraviolet in the white light. 
C)  blue and violet do not spread out very much as a result of passing through the prism. 
D)  red is absorbed more than is the rest of the spectrum.

Question 14

The total amount of radiation emitted by a heated blackbody depends on its temperature and

Accepted Answer

A)  how much surface area it has. 
B)  how much volume it has. 
C)  its color. 
D)  its chemical composition. 
A)  how much surface area it has. 
B)  how much volume it has. 
C)  its color. 
D)  its chemical composition.

Question 15

An ideal blackbody in physics and astronomy is an object that

Accepted Answer

A)  emits only infrared light and hence appears black to the eye. 
B)  does not emit or absorb any electromagnetic radiation. 
C)  absorbs and emits electromagnetic radiation at all wavelengths. 
D)  absorbs all electromagnetic radiation but emits none. 
A)  emits only infrared light and hence appears black to the eye. 
B)  does not emit or absorb any electromagnetic radiation. 
C)  absorbs and emits electromagnetic radiation at all wavelengths. 
D)  absorbs all electromagnetic radiation but emits none.

Question 16

The total radiant energy emitted from the entire surface of a blackbody is proportional to what power of the blackbody's Kelvin temperature?

Accepted Answer

A)  T 
B)  1/T 
C)  T2 
D)  T4 
A)  T 
B)  1/T 
C)  T2 
D)  T4

Question 17

A blackbody is an idealized object in physics and astronomy that

Accepted Answer

A)  reflects no light and emits light in a manner determined by its temperature. 
B)  reflects and emits radiation in a manner that is completely determined by its temperature. 
C)  reflects and emits light with the same intensity at all wavelengths. 
D)  does not emit or reflect any radiation. 
A)  reflects no light and emits light in a manner determined by its temperature. 
B)  reflects and emits radiation in a manner that is completely determined by its temperature. 
C)  reflects and emits light with the same intensity at all wavelengths. 
D)  does not emit or reflect any radiation.

Question 18

A star whose surface temperature is 100,000 K will emit a spectrum whose peak wavelength is at

Accepted Answer

A)  ultraviolet wavelengths. 
B)  X-ray wavelengths. 
C)  visible wavelengths. 
D)  infrared wavelengths. 
A)  ultraviolet wavelengths. 
B)  X-ray wavelengths. 
C)  visible wavelengths. 
D)  infrared wavelengths.

Question 19

Two different isotopes of the element selenium will have the same number of

Accepted Answer

A)  protons but a different number of neutrons. 
B)  protons but a different number of electrons. 
C)  protons and neutrons, but they are arranged differently in the nucleus. 
D)  neutrons but a different number of protons. 
A)  protons but a different number of neutrons. 
B)  protons but a different number of electrons. 
C)  protons and neutrons, but they are arranged differently in the nucleus. 
D)  neutrons but a different number of protons.

Question 20

When astronomers look for evidence of hydrogen gas in the spectra of the Sun, the planets, or the nearby stars, the positions of the spectral features or "lines" due to hydrogen are in

Accepted Answer

A)  a pattern in which the positions of the lines depend on the temperature of the source. 
B)  the same pattern for the Sun and for planetary sources but very different for stars at larger distances because of absorption of light by the interstellar matter. 
C)  the same characteristic pattern as seen in the laboratory, a pattern unique to hydrogen. 
D)  a pattern that depends on the location of the planet or star and that can be reproduced only with difficulty in the laboratory. 
A)  a pattern in which the positions of the lines depend on the temperature of the source. 
B)  the same pattern for the Sun and for planetary sources but very different for stars at larger distances because of absorption of light by the interstellar matter. 
C)  the same characteristic pattern as seen in the laboratory, a pattern unique to hydrogen. 
D)  a pattern that depends on the location of the planet or star and that can be reproduced only with difficulty in the laboratory.

Where does the Paschen series of spectral lines from hydrogen gas appear in the electromagnetic spectrum?

The Stefan-Boltzmann law, which relates the energy per unit area F emitted by an object to its temperature T, F = $\sigma$ T⁴, is obeyed by what kind of object?

If a continuous spectrum of ultraviolet radiation passes through a tube of cool hydrogen gas, what happens to its spectrum?

In his scattering experiment, Ernest Rutherford expected that the alpha particles he was using as bullets would easily penetrate his gold foil target with no backscatter. What was the actual result of the experiment?

Figure 4-2 in the text shows that a blackbody with a temperature of 3000 K emits radiation that peaks at a wavelength much longer than wavelengths in the visible part of the spectrum. This means that the object

The normal temperature of the melting point of water ice is

The amount of radiation emitted by a blackbody depends on all of these properties of the blackbody EXCEPT

Which of these equations represents the dependence of the total energy flux F of radiation emitted per unit area by a blackbody (e.g., star) on its temperature T with $\sigma$ a constant?

The proton, the nucleus of the hydrogen atom, has a mass that exceeds that of the electron by approximately what factor?

A piece of iron is heated from 400 K to 800 K. The total energy emitted per second by this iron will increase by a factor of

One problem with using a glass prism to produce a spectrum from white light is that

The total amount of radiation emitted by a heated blackbody depends on its temperature and

An ideal blackbody in physics and astronomy is an object that

The total radiant energy emitted from the entire surface of a blackbody is proportional to what power of the blackbody's Kelvin temperature?

A blackbody is an idealized object in physics and astronomy that

A star whose surface temperature is 100,000 K will emit a spectrum whose peak wavelength is at

Two different isotopes of the element selenium will have the same number of

When astronomers look for evidence of hydrogen gas in the spectra of the Sun, the planets, or the nearby stars, the positions of the spectral features or "lines" due to hydrogen are in

Discovering the Night Sky

Gravitation and the Motion of the Planets

Light and Telescopes

Exoplanets and the Formation of Planetary Systems

Formation of the Solar System

Earth and the Moon

The Other Terrestrial Planets

The Outer Planets

Vagabonds of the Solar System

The Sun: Our Extraordinary Star

Characterizing Stars

The Lives of Stars From Birth Through Middle Age

The Death of Stars

Black Holes: Matters of Gravity

The Milky Way Galaxy

Galaxies

Quasars and Other Active Galaxies

Cosmology

Astrobiology

Filters

Exam 4: Atomic Physics and Spectra

Where does the Paschen series of spectral lines from hydrogen gas appear in the electromagnetic spectrum?

The Stefan-Boltzmann law, which relates the energy per unit area F emitted by an object to its temperature T, F = σ\sigmaσ T4, is obeyed by what kind of object?

If a continuous spectrum of ultraviolet radiation passes through a tube of cool hydrogen gas, what happens to its spectrum?

In his scattering experiment, Ernest Rutherford expected that the alpha particles he was using as bullets would easily penetrate his gold foil target with no backscatter. What was the actual result of the experiment?

Figure 4-2 in the text shows that a blackbody with a temperature of 3000 K emits radiation that peaks at a wavelength much longer than wavelengths in the visible part of the spectrum. This means that the object

The normal temperature of the melting point of water ice is

The amount of radiation emitted by a blackbody depends on all of these properties of the blackbody EXCEPT

Which of these equations represents the dependence of the total energy flux F of radiation emitted per unit area by a blackbody (e.g., star) on its temperature T with σ\sigmaσ a constant?

The proton, the nucleus of the hydrogen atom, has a mass that exceeds that of the electron by approximately what factor?

A piece of iron is heated from 400 K to 800 K. The total energy emitted per second by this iron will increase by a factor of

One problem with using a glass prism to produce a spectrum from white light is that

The total amount of radiation emitted by a heated blackbody depends on its temperature and

An ideal blackbody in physics and astronomy is an object that

The total radiant energy emitted from the entire surface of a blackbody is proportional to what power of the blackbody's Kelvin temperature?

A blackbody is an idealized object in physics and astronomy that

A star whose surface temperature is 100,000 K will emit a spectrum whose peak wavelength is at

Two different isotopes of the element selenium will have the same number of

When astronomers look for evidence of hydrogen gas in the spectra of the Sun, the planets, or the nearby stars, the positions of the spectral features or "lines" due to hydrogen are in

Discovering the Night Sky

Gravitation and the Motion of the Planets

Light and Telescopes

Exoplanets and the Formation of Planetary Systems

Formation of the Solar System

Earth and the Moon

The Other Terrestrial Planets

The Outer Planets

Vagabonds of the Solar System

The Sun: Our Extraordinary Star

Characterizing Stars

The Lives of Stars From Birth Through Middle Age

The Death of Stars

Black Holes: Matters of Gravity

The Milky Way Galaxy

Galaxies

Quasars and Other Active Galaxies

Cosmology

Astrobiology

Filters

The Stefan-Boltzmann law, which relates the energy per unit area F emitted by an object to its temperature T, F = $\sigma$ T⁴, is obeyed by what kind of object?

Which of these equations represents the dependence of the total energy flux F of radiation emitted per unit area by a blackbody (e.g., star) on its temperature T with $\sigma$ a constant?