Chapter 31: Properties of light
Section 31-1: The Speed of Light, and
Concept Check 31-1
You are attempting to reproduce Fizeau’s determination of the
speed of light. Using a wheel that has 720 teeth, light is
observed when the wheel rotates and light is reflected
between the teeth from a distant mirror. You assume that the
time taken for the light to travel from the wheel to the mirror
and back is the time for the wheel to rotate 1/720 of a
revolution. You obtain a result for the speed of light which is 7
percent too low. What is the most likely source of error to
account for this discrepancy?
A. You have miscounted the teeth.
B. You have not measured the angular speed correctly.
C. There are 720 teeth, but there are also 720 gaps, so the
width of a tooth is less than 1/720 of the circumference
of the wheel.
D. You have not measured the distance to the mirror
correctly.
E. Light travels 7% slower in air than in a vacuum.
You are attempting to reproduce Fizeau’s determination of the
speed of light. Using a wheel that has 720 teeth, light is
observed when the wheel rotates and light is reflected
between the teeth from a distant mirror. You assume that the
time taken for the light to travel from the wheel to the mirror
and back is the time for the wheel to rotate 1/720 of a
revolution. You obtain a result for the speed of light which is 7
percent too low. What is the most likely source of error to
account for this discrepancy?
A. You have miscounted the teeth.
B. You have not measured the angular speed correctly.
C. There are 720 teeth, but there are also 720 gaps, so
the width of a tooth is less than 1/720 of the
circumference of the wheel.
D. You have not measured the distance to the mirror
correctly.
E. Light travels 7% slower in air than in a vacuum.
Mission Control sends a brief wake-up call to
astronauts in a distant spaceship. Five
seconds after the call is sent, Mission Control
hears the waking groans of the astronauts.
How far away (at most) from the earth is the
spaceship?
A. 7.5 ×108 m
B. 15 × 108 m
C. 30 × 108 m
D. 45 × 108 m
E. There is no upper limit on the distance.
Mission Control sends a brief wake-up call to
astronauts in a distant spaceship. Five
seconds after the call is sent, Mission Control
hears the waking groans of the astronauts.
How far away (at most) from the earth is the
spaceship?
A. 7.5 ×108 m
B. 15 × 108 m
C. 30 × 108 m
D. 45 × 108 m
E. There is no upper limit on the distance.
The speed of ultraviolet radiation in free
space compared with the speed of visible
radiation in free space is
A. greater.
B. the same.
C. less.
The speed of ultraviolet radiation in free
space compared with the speed of visible
radiation in free space is
A. greater.
B. the same.
C. less.
The speed of radio waves in free space
compared with the speed of visible radiation
in free space is
A. greater.
B. the same.
C. less.
The speed of radio waves in free space
compared with the speed of visible radiation
in free space is
A. greater.
B. the same.
C. less.
Ultra fast pulse lasers can emit pulses of the
order 10 fs. The physical length of each
pulse that is 10 fs long in duration is
A. 1.0 μm
B. 2.0 μm
C. 3.0 μm
D. 9.0 μm
E. 12.0 μm
Ultra fast pulse lasers can emit pulses of the
order 10 fs. The physical length of each
pulse that is 10 fs long in duration is
A. 1.0 μm
B. 2.0 μm
C. 3.0 μm
D. 9.0 μm
E. 12.0 μm
Chapter 31: Properties of light
Section 31-3: Reflection and Refraction
As light passes from one medium into
another, the angle of refraction is smaller in
the medium with the _____ index of
refraction and _____ speed of light.
A. larger; lower
B. larger; higher
C. smaller; lower
D. smaller; higher
As light passes from one medium into
another, the angle of refraction is smaller in
the medium with the _____ index of
refraction and _____ speed of light.
A. larger; lower
B. larger; higher
C. smaller; lower
D. smaller; higher
A glass block with index of refraction 1.50 is
immersed in water whose index of refraction
is 1.33. The critical angle at the glass–water
interface is
A. 6.5º
B. 41.9º
C. 48.8º
D. 56.3º
E. 62.5º
A glass block with index of refraction 1.50 is
immersed in water whose index of refraction
is 1.33. The critical angle at the glass–water
interface is
A. 6.5º
B. 41.9º
C. 48.8º
D. 56.3º
E. 62.5º
Which of the following statements is true
about the speeds of the various colors of
light in glass?
A. All colors of light have the same speed
in glass.
B. Violet has the highest speed, red the
lowest.
C. Red has the highest speed, violet the
lowest.
Which of the following statements is true
about the speeds of the various colors of
light in glass?
A. All colors of light have the same speed
in glass.
B. Violet has the highest speed, red the
lowest.
C. Red has the highest speed, violet
the lowest.
A light wave traveling at speed v1 in medium 1
passes into medium 2 where its speed is v2.
By which of the following equations is the
frequency f1 of the wave in medium 1 related to
its frequency f2 in medium 2?
A. f1v2 = f2v1
B. f1 = f2
C. f1v1 = f2v2
A light wave traveling at speed v1 in medium 1
passes into medium 2 where its speed is v2.
By which of the following equations is the
frequency f1 of the wave in medium 1 related to
its frequency f2 in medium 2?
A. f1v2 = f2v1
B. f1 = f2
C. f1v1 = f2v2
Light that has been traveling in a medium
with an index of refraction n2 is incident on
the boundary surface of another medium with
an index of refraction n1. Given a sufficient
angle of incidence, which of the following
conditions must be satisfied for total internal
reflection to occur?
A. n1 < n2
B. n1 > n2
C. n1 = n2
Light that has been traveling in a medium
with an index of refraction n2 is incident on
the boundary surface of another medium with
an index of refraction n1. Given a sufficient
angle of incidence, which of the following
conditions must be satisfied for total internal
reflection to occur?
A. n1 < n2
B. n1 > n2
C. n1 = n2
You are trying to catch fish by using a spear.
You observe a large fish a couple of meters
in front of you and a meter below the water
surface. In order to hit the fish with your
spear you must aim (assume that the fish is
stationary and does not swim away in fright)
A. directly at the point where you see the
fish.
B. slightly above the point where you see
the fish.
C. slightly below the point where you see
the fish.
You are trying to catch fish by using a spear.
You observe a large fish a couple of meters
in front of you and a meter below the water
surface. In order to hit the fish with your
spear you must aim (assume that the fish is
stationary and does not swim away in fright)
A. directly at the point where you see the
fish.
B. slightly above the point where you see
the fish.
C. slightly below the point where you
see the fish.
You see a fish in water at an apparent depth
of 1.83 m. The actual depth of the fish, if the
index of refraction of the water relative to air
is 4/3, must be
A. 3.81 cm
B. 61.0 cm
C. 1.37 m
D. 1.83 m
E. 2.44 m
You see a fish in water at an apparent depth
of 1.83 m. The actual depth of the fish, if the
index of refraction of the water relative to air
is 4/3, must be
A. 3.81 cm
B. 61.0 cm
C. 1.37 m
D. 1.83 m
E. 2.44 m
A ray of light passes from air into water,
striking the surface of the water with an
angle of incidence of 45º. Which of the
following four quantities change as the light
enters the water: (1) wavelength, (2)
frequency, (3) speed of propagation, and (4)
direction of propagation?
A. 1 and 2 only
B. 2, 3, and 4 only
C. 1, 3, and 4 only
D. 3 and 4 only
E. 1, 2, 3, and 4
A ray of light passes from air into water,
striking the surface of the water with an
angle of incidence of 45º. Which of the
following four quantities change as the light
enters the water: (1) wavelength, (2)
frequency, (3) speed of propagation, and (4)
direction of propagation?
A. 1 and 2 only
B. 2, 3, and 4 only
C. 1, 3, and 4 only
D. 3 and 4 only
E. 1, 2, 3, and 4
A light ray makes an angle of 42º with the
normal to a glass-water surface on the glass
side of the surface. The angle q in the water
is
A. 42º
B. 36º
C. 63º
D. 49º
E. 27º
A light ray makes an angle of 42º with the
normal to a glass-water surface on the glass
side of the surface. The angle q in the water
is
A. 42º
B. 36º
C. 63º
D. 49º
E. 27º
In the laboratory you used the spectrometer
to determine the indices of refraction of
various wavelengths of light. Which curve
could represent a plot of the index of
refraction as a function of the wavelength of
the light?
In the laboratory you used the spectrometer
to determine the indices of refraction of
various wavelengths of light. Which curve
could represent a plot of the index of
refraction as a function of the wavelength of
the light?
Monochromatic light is incident on the prism
at the proper angle for minimum deviation.
The emergent ray passes through which
point?
Monochromatic light is incident on the prism
at the proper angle for minimum deviation.
The emergent ray passes through which
point?
Light travels in a medium of index of
refraction n', passes into a medium of index
n", where n" > n', and then into air, where nair
< n' < n". Which ray correctly shows the light
path?
Light travels in a medium of index of
refraction n', passes into a medium of index
n", where n" > n', and then into air, where nair
< n' < n". Which ray correctly shows the light
path?
Light from an underwater source at O
impinges upon a water-air interface. Which
label shows the critical angle?
Light from an underwater source at O
impinges upon a water-air interface. Which
label shows the critical angle?
The light ray that passes through the prism
and emerges at the angle of minimum
deviation for that color is
A. red
B. yellow
C. green
D. blue
E. violet
The light ray that passes through the prism
and emerges at the angle of minimum
deviation for that color is
A. red
B. yellow
C. green
D. blue
E. violet
An air prism is immersed in water. A ray of
monochromatic light strikes one face as
shown. Which arrow shows the emerging
ray?
An air prism is immersed in water. A ray of
monochromatic light strikes one face as
shown. Which arrow shows the emerging
ray?
Which label shows the angle of minimum
deviation?
Which label shows the angle of minimum
deviation?
The figure shows the electric field strength
versus distance for light that is normally
incident on and transmitted through a
refractive medium. The index of refraction of
this medium is
A. 1.0
B. 1.5
C. 2.0
D. 0.67
E. 3.0
The figure shows the electric field strength
versus distance for light that is normally
incident on and transmitted through a
refractive medium. The index of refraction of
this medium is
A. 1.0
B. 1.5
C. 2.0
D. 0.67
E. 3.0
A ray of light in glass is incident on a glass–
air interface as shown. You would expect a
ray to pass through
A. point 1 only.
B. point 3 only.
C. point 4 only.
D. points 2 and 4.
E. points 1 and 4.
A ray of light in glass is incident on a glass–
air interface as shown. You would expect a
ray to pass through
A. point 1 only.
B. point 3 only.
C. point 4 only.
D. points 2 and 4.
E. points 1 and 4.
The rays in the figure are
reflected and refracted at the
front and back surfaces of the
glass. Which of the following
is true of the angles of these
rays relative to normal?
A. 1 = 2 = 3 = 4
B. 1 = 2; 3 = 4; but 1 ≠ 3
C. 1 = 2 = 3; but 4 ≠ 1
D. 1 = 4; but 2 ≠ 4
E. 1 ≠ 2 ≠ 3 ≠ 4
The rays in the figure are
reflected and refracted at the
front and back surfaces of the
glass. Which of the following
is true of the angles of these
rays relative to normal?
A. 1 = 2 = 3 = 4
B. 1 = 2; 3 = 4; but 1 ≠ 3
C. 1 = 2 = 3; but 4 ≠ 1
D. 1 = 4; but 2 ≠ 4
E. 1 ≠ 2 ≠ 3 ≠ 4
A plane
wavefront of
light (AA')
approaches an
air–water
interface as
shown. n < n'.
Which diagram
best shows the
refracted wave?
A plane
wavefront of
light (AA')
approaches an
air–water
interface as
shown. n < n'.
Which diagram
best shows the
refracted wave?
A fiber optic is made by cladding a thin fiber
core of refractive index n1 = 1.45 with a
material of refractive index n2 = 1.38. What
is the critical angle at the core-cladding
interface?
A. 44º
B. 46º
C. 55º
D. 72º
E. None of these is correct.
A fiber optic is made by cladding a thin fiber
core of refractive index n1 = 1.45 with a
material of refractive index n2 = 1.38. What
is the critical angle at the core-cladding
interface?
A. 44º
B. 46º
C. 55º
D. 72º
E. None of these is correct.
A fiber optic is made by cladding a thin fiber
core of refractive index n1 = 1.45 with a
material of refractive index n2 = 1.38. What
is the maximum incident angle, θ, so that the
light ray is totally internally reflected inside
the fiber?
A. 24.1º
B. 26.4º
C. 28.2º
D. 30.3º
E. 32.7º
air
n
1

n2
A fiber optic is made by cladding a thin fiber
core of refractive index n1 = 1.45 with a
material of refractive index n2 = 1.38. What
is the maximum incident angle, θ, so that the
light ray is totally internally reflected inside
the fiber?
A. 24.1º
B. 26.4º
C. 28.2º
D. 30.3º
E. 32.7º
air
n
1

n2
Chapter 31: Properties of light
Section 31-4: Polarization
Light is an electromagnetic wave. When visible
light is plane polarized,
A. the electric-field vector is parallel to the
magnetic-field vector.
B. the electric-field vector is parallel to the direction
of propagation.
C. the electric-field vector is in a fixed direction
perpendicular to the direction of propagation, but
the magnetic-field vector may be in any direction.
D. the electric-field vector is in a fixed direction
perpendicular to the direction of propagation, and
the magnetic-field vector is perpendicular to the
electric-field vector.
E. None of these is correct.
Light is an electromagnetic wave. When visible
light is plane polarized,
A. the electric-field vector is parallel to the
magnetic-field vector.
B. the electric-field vector is parallel to the direction
of propagation.
C. the electric-field vector is in a fixed direction
perpendicular to the direction of propagation, but
the magnetic-field vector may be in any direction.
D. the electric-field vector is in a fixed direction
perpendicular to the direction of propagation,
and the magnetic-field vector is perpendicular
to the electric-field vector.
E. None of these is correct.
Two polarizers have their transmission axes
at an angle θ. Unpolarized light of intensity I
is incident on the first polarizer. What is the
intensity of the light transmitted by the
second polarizer?
A. I cos2 θ
B. 0.5I cos2 θ
C. 0.25I cos2 θ
D. I cos θ
E. 0.25I cos θ
Two polarizers have their transmission axes
at an angle θ. Unpolarized light of intensity I
is incident on the first polarizer. What is the
intensity of the light transmitted by the
second polarizer?
A. I cos2 θ
B. 0.5I cos2 θ
C. 0.25I cos2 θ
D. I cos θ
E. 0.25I cos θ
Which of the following is not a phenomenon
by which polarized light can be produced
from unpolarized light?
A. absorption
B. reflection
C. birefringence
D. diffraction
E. scattering
Which of the following is not a phenomenon
by which polarized light can be produced
from unpolarized light?
A. absorption
B. reflection
C. birefringence
D. diffraction
E. scattering
The index of refraction of a sample of glass
cannot be determined by measuring the
A. Brewster's angle.
B. critical angle.
C. angle of minimum deviation.
D. ratio of true to apparent depth.
E. angle of dispersion between red and
violet light.
The index of refraction of a sample of glass
cannot be determined by measuring the
A. Brewster's angle.
B. critical angle.
C. angle of minimum deviation.
D. ratio of true to apparent depth.
E. angle of dispersion between red
and violet light.
If you look at a dot on a piece of paper through a
calcite crystal lying on the paper, you will see two
images of the dot, one of which appears to be
nearer to you than the other. From this evidence
you can conclude that
A. the beams from both images are polarized.
B. calcite has different indices of refraction for
the two beams.
C. there is interference between the two beams.
D. the calcite has increased the resolving power
of your eye.
E. the appearance is due to diffraction.
If you look at a dot on a piece of paper through a
calcite crystal lying on the paper, you will see two
images of the dot, one of which appears to be
nearer to you than the other. From this evidence
you can conclude that
A. the beams from both images are polarized.
B. calcite has different indices of refraction
for the two beams.
C. there is interference between the two beams.
D. the calcite has increased the resolving power
of your eye.
E. the appearance is due to diffraction.
What taking a picture of a highly reflecting
surface, it is desirable to use a polarizer in
front of the camera to cut down on the
“glare”. Suppose you are taking a picture of
a lake where the water is very still. The
polarizing axis of the polarizer should ideally
be oriented
A. horizontally.
B. vertically.
What taking a picture of a highly reflecting
surface, it is desirable to use a polarizer in
front of the camera to cut down on the
“glare”. Suppose you are taking a picture of
a lake where the water is very still. The
polarizing axis of the polarizer should ideally
be oriented
A. horizontally.
B. vertically.
In any wave motion, dependence of velocity
on wavelength is called
A. polarization
B. deviation
C. dispersion
D. diffraction
E. scattering
In any wave motion, dependence of velocity
on wavelength is called
A. polarization
B. deviation
C. dispersion
D. diffraction
E. scattering
Polarized light cannot be produced by
A. dispersion
B. dichroism
C. reflection
D. scattering
E. refraction
Polarized light cannot be produced by
A. dispersion
B. dichroism
C. reflection
D. scattering
E. refraction
One would not attempt to polarize light by
A. selective absorption.
B. reflection from a surface.
C. passage through a narrow slit.
D. scattering.
E. double refraction.
One would not attempt to polarize light by
A. selective absorption.
B. reflection from a surface.
C. passage through a narrow slit.
D. scattering.
E. double refraction.
Light is circularly polarized if
A. the cross section of a spherical wave front
is polarized.
B. it consists of two plane-polarized waves
that are out of phase with each other by
90º.
C. it is refracted by a medium that has a high
index of refraction.
D. it is reflected at the critical angle and
polarized.
E. it is polarized by scattering from
molecules.
Light is circularly polarized if
A. the cross section of a spherical wave front
is polarized.
B. it consists of two plane-polarized waves
that are out of phase with each other by
90º.
C. it is refracted by a medium that has a high
index of refraction.
D. it is reflected at the critical angle and
polarized.
E. it is polarized by scattering from
molecules.
The optical phenomenon that is usually cited
as demonstrating the transverse wave
nature of light is
A. dispersion
B. interference
C. reflection
D. polarization
E. refraction
The optical phenomenon that is usually cited
as demonstrating the transverse wave
nature of light is
A. dispersion
B. interference
C. reflection
D. polarization
E. refraction
A ray of light (ab) is incident on the surface of a piece
of glass at such an angle that the reflected ray (bc) is
totally polarized. The directed line segment that
represents the refracted ray is
A. 1
B. 2
C. 3
D. 4
E. None of these is correct.
A ray of light (ab) is incident on the surface of a piece
of glass at such an angle that the reflected ray (bc) is
totally polarized. The directed line segment that
represents the refracted ray is
A. 1
B. 2
C. 3
D. 4
E. None of these is correct.
Of the following quantities, the one that is
independent of the frequency of light is the
A. polarizing angle.
B. critical angle.
C. angle of minimum deviation.
D. angle of refraction.
E. angle of reflection.
Of the following quantities, the one that is
independent of the frequency of light is the
A. polarizing angle.
B. critical angle.
C. angle of minimum deviation.
D. angle of refraction.
E. angle of reflection.
A ray of unpolarized light is incident on a glass
block at an angle of incidence in such a way that
the reflected ray is completely plane polarized.
Which ray best represents the refracted ray?
A ray of unpolarized light is incident on a glass
block at an angle of incidence in such a way that
the reflected ray is completely plane polarized.
Which ray best represents the refracted ray?
Sound waves differ from light waves in many
respects. One important difference is that
sound waves cannot
A. be refracted.
B. be reflected.
C. show interference.
D. show diffraction.
E. be polarized.
Sound waves differ from light waves in many
respects. One important difference is that
sound waves cannot
A. be refracted.
B. be reflected.
C. show interference.
D. show diffraction.
E. be polarized.
Which of the following is not a property of all
waves?
A. refraction
B. diffraction
C. reflection
D. interference
E. polarization
Which of the following is not a property of all
waves?
A. refraction
B. diffraction
C. reflection
D. interference
E. polarization
When light is reflected from a plane surface of
glass at the polarizing angle, the
A. reflected ray is at right angles to the incident
ray.
B. angle of reflection is equal to the angle of
refraction.
C. incident ray is at right angles to the refracted
ray.
D. reflected ray is at right angles to the refracted
ray.
E. intensity of the reflected light is a maximum.
When light is reflected from a plane surface of
glass at the polarizing angle, the
A. reflected ray is at right angles to the incident
ray.
B. angle of reflection is equal to the angle of
refraction.
C. incident ray is at right angles to the refracted
ray.
D. reflected ray is at right angles to the
refracted ray.
E. intensity of the reflected light is a maximum.
The angle of incidence that will cause the
unpolarized light to be reflected as
completely plane-polarized light is called
A. Brewster's angle.
B. Young's angle.
C. Snells's angle.
D. Huygens' angle.
E. Fraunhofer's angle.
The angle of incidence that will cause the
unpolarized light to be reflected as
completely plane-polarized light is called
A. Brewster's angle.
B. Young's angle.
C. Snells's angle.
D. Huygens' angle.
E. Fraunhofer's angle.
If the index of refraction of a glass plate is
1.45, the angle of incidence that will cause
the unpolarized light to be reflected as
completely plane polarized light is
A. 8.25º
B. 34.6º
C. 45.0º
D. 55.4º
E. 81.7º
If the index of refraction of a glass plate is
1.45, the angle of incidence that will cause
the unpolarized light to be reflected as
completely plane polarized light is
A. 8.25º
B. 34.6º
C. 45.0º
D. 55.4º
E. 81.7º
The plane of polarization of the reflected
light lies
A. parallel to the screen.
B. at 45º with respect to the screen.
C. perpendicular to the screen.
The plane of polarization of the reflected
light lies
A. parallel to the screen.
B. at 45º with respect to the screen.
C. perpendicular to the screen.
Chapter 31: Properties of light
Section 31-5: Derivation of the Laws of
Reflection and Refraction
Huygens' theory for the construction of wavefronts
states that
A. the angle of incidence is always less than the
angle of refraction.
B. the time required for light to travel from one
point to another is either a maximum or
minimum.
C. only parallel light produces interference and
diffraction.
D. each point on a wavefront is itself the source
of a secondary spherical wave.
E. all wavefronts are spherical.
Huygens' theory for the construction of wavefronts
states that
A. the angle of incidence is always less than the
angle of refraction.
B. the time required for light to travel from one
point to another is either a maximum or
minimum.
C. only parallel light produces interference and
diffraction.
D. each point on a wavefront is itself the
source of a secondary spherical wave.
E. all wavefronts are spherical.
The principle of superposition states:
A. The effect observed at each point of a wave made up
of two or more waves is the sum of the effects that
the individual waves would produce at that point.
B. Huygens' wavelets cannot be allowed to extend
across regions where the phase velocity of the wave
changes abruptly.
C. Sources of radiation whose phase angles are
maintained at constant differences are said to be
coherent.
D. A characteristic phenomenon of wave propagation is
the tendency of a wave to expand around and behind
any obstacles it chances to encounter.
E. A good source of waves at a particular frequency is a
good detector of waves at the same frequency.
The principle of superposition states:
A. The effect observed at each point of a wave made
up of two or more waves is the sum of the effects
that the individual waves would produce at that
point.
B. Huygens' wavelets cannot be allowed to extend
across regions where the phase velocity of the wave
changes abruptly.
C. Sources of radiation whose phase angles are
maintained at constant differences are said to be
coherent.
D. A characteristic phenomenon of wave propagation is
the tendency of a wave to expand around and behind
any obstacles it chances to encounter.
E. A good source of waves at a particular frequency is a
good detector of waves at the same frequency.
"To find the value of the resultant
displacement for overlapping waves at any
point at a particular instant, it is only
necessary to add the values of the
displacements for the individual waves."
This is a statement of
A. Huygens' principle.
B. the principle of superposition.
C. Bernoulli's principle.
D. the principle of dispersion.
E. Newton's theory of light.
"To find the value of the resultant
displacement for overlapping waves at any
point at a particular instant, it is only
necessary to add the values of the
displacements for the individual waves."
This is a statement of
A. Huygens' principle.
B. the principle of superposition.
C. Bernoulli's principle.
D. the principle of dispersion.
E. Newton's theory of light.
A light wave is like a sound wave in that both
A. are longitudinal waves.
B. are means of transmitting energy.
C. are transverse waves.
D. require a material medium for
propagation.
E. have the same velocity in air.
A light wave is like a sound wave in that both
A. are longitudinal waves.
B. are means of transmitting energy.
C. are transverse waves.
D. require a material medium for
propagation.
E. have the same velocity in air.
Chapter 31: Properties of light
Section 31-8: Sources of Light
If the wavelength l of the incident light is
large compared with the size of an atom, the
probability of elastic scattering upon the
atom varies as
A. λ
B. λ4
C. λ–4
D. λ2
E. λ–3
If the wavelength l of the incident light is
large compared with the size of an atom, the
probability of elastic scattering upon the
atom varies as
A. λ
B. λ4
C. λ–4
D. λ2
E. λ–3
The lifetime of a typical excited atomic
energy state is of the order of
A. 10–6 s
B. 10–7 s
C. 10–8 s
D. 10–9 s
E. 10–10 s
The lifetime of a typical excited atomic
energy state is of the order of
A. 10–6 s
B. 10–7 s
C. 10–8 s
D. 10–9 s
E. 10–10 s