Chapter 29-34 Test
The half life of carbon 14 is 5730 years. If a 1-gram sample of old carbon is 1/8 as radioactive as 1-gram of a current sample, then the age of the old sample is about
17,200 years
When radium (A = 88) emits an alpha particle, the resulting nucleus has atomic number
86
When U-235 undergoes fission, the two nuclei that result have a total of
92 protons
Some double-pane airplane windows darken when the inner pane is rotated. The panes are
Polaroid filters
Which element has the smaller critical mass; U-235 that releases 2.5 neutrons per fission, or Pu-239 that releases 2.7 neutrons per fission?
Pu-239
a nucleon is either
a proton or neutron
A new theory conforms to the correspondence principle when it
accounts for verified results of the old theory
According to quantum physics, measuring the velocity of a tiny particle with an electromagnet
affects the velocity of the particle
the correspondence principle applies to
all good theories
Sometimes a flashlight filament glows red instead of white. This indicates a lowness of
all of these (current in the filament. filament temperature. battery strength)
A radiation detector measures the radioactivity of a piece of radium by catching and counting alpha particles it emits. According to physics, making this measurement affects the
alpha particles that are caught
quantum uncertainties are most predominant for simultaneously measuring the speed and location of
an electron
the function of polarizing filters in viewing 3-D slides or movies is to provide each eye
an independent left or right-hand view
an atom with an imbalance of electrons to protons is
an ion
The vibrational direction of the electron and the plane of polarization of the light it emits
are the same
Radioactivity in the world is something
as old as the world itself
The polarization axes of glasses for 3-D viewing are
at right angles to each other
If an alpha particle and a beta particle have the same energy, which particle will penetrate farther into an object?
beta particle
the hottest star is the star that glows
blue
which body is heated in its interior by nuclear processes
both (sun and earth)
when an alpha particle is ejected from a nucleus, the nucleus then has less
both of these (mass and charge)
a beam of electrons has
both of these (particle and wave properties)
if a proton and an electron have identical momentum, the longer wavelength belongs to the
both the same (electron & proton)
what is it that electrons have that protons always have in equal magnitude
charge
energy released by the sun results from the process wherein atomic nuclei
combine
A hologram is simply a
complex diffraction grating
We now consider the orbital model of the atom to be
defective and oversimplified, but still useful
some alpha particles fired through a gold foil bounce backward by
electrostatic repulsion when close to gold nuclei
once an alpha particle is outside the nucleus it is
electrostatically repelled
which light source is more energy-efficient
fluorescent lamp
Which experiences the least electrical force in an electric field?
gamma ray
x-rays are similar to
gamma rays
A device that is used primarily to detect nuclear radiation is a
geiger counter
a chain reaction grows when the average number of liberated neutrons which go on to cause further fissions is
greater than one
Plutonium is not found in any appreciable amounts in natural ore deposits because it
has a short half life
When the hydrogen isotope tritium-3 emits a beta particle, it becomes an isotope of
helium
The most abundant element in the universe is
hydrogen
when a lump of uranium is broken into smaller pieces, the total surface area of the lump
increases
a nucleon has the least mass in the nucleus of
iron
uranium-235, uranium-239 and uranium-239 are different
isotopes
The energy release in both fission and fusion is mainly in the form of
kinetic energy of fragments
In gaseous form, at the same temperature, the average speed of U-238 compared to the speed of U-235 is
less
which of the following has the longer wavelength
low energy electron
The spectral lines are more distinct when viewed in a mercury vapor lamp under
low pressure
in the process of fluorescence, the input is high-frequency light and the output is
lower-frequency light
in the photoelectric effect, the greater the frequency of the illuminating light, the greater the
maximum velocity of ejected electrons
which of the following are conserved when a photon collides with an electron
momentum and energy
the amount of radiation we personally encounter that originates in the earth's and the atomosphere's natural background is
more than half
If iron were used as nuclear fuel, it would be best
neither fused nor fissioned
when a gamma ray is emitted by a nucleus, the nucleus then has appreciably less
neither of these
different isotopes of an element have different numbers of
neutrons
there is a greater proportion of carbon 14 in
new bones
the discreteness of energy levels is better understood by considering the electrons to be
none of these
when thorium (A=90) emits a beta particle, the resulting nucleus has atomic number
none of these (91)
an inventor proposes to equip an office with a polarized source of background music and let those who prefer not to hear it wear polarizing earplugs. his idea is
nonsense - you can't polarize a sound wave
the half-life on an isotope is one day. at the end of three days, how much of the isotope remains
one-eighth
in the double-slit experiment with electrons, the electrons arrive at the screen in a
particle-like way with a pattern that is wave-like
The phenomenon that can be explained only in terms of the particle model of light is
photoelectric effect
Which experiment best demonstrates the particle-like nature of light?
photoelectric effect
electric forces within an atomic nucleus tend to
push it apart
an excited atom decays to its ground state and emits a photon of green light. if instead the atom decays to an intermediate state, then the light emitted could be
red
Fissioning a lead nucleus yields a net
release of energy
Fusing two helium nuclei yields a net
release of energy
an electron in an excited state could give off
several photons in a series of transitions to the ground state
Compared to the wavelengths of visible light, the wavelengths of matter waves are relatively
small
Which shape uses the smallest amount of material when creating a critical mass
sphere
The quantum-mechanical probability cloud for the electron in the hydrogen atom has an average radius
that agrees with the orbital radius of Bohr
The main reason electrons occupy discrete orbits in an atom is because
the circumference of each orbit is an integral multiple of electron wavelengths
The half lives of elements beyond uranium are too short for these elements to occur in natural deposits. But elements below uranium that have equally short half lives do occur in natural deposits. This is because they are
the products of uranium decay
Compared to the diameter of a zirconium atom (A = 40), the diameter of a mercury atom (A = 80) is approximately
the same size
***ushima is
the site of several nuclear reactors in japan
light behaves primarily as a wave when it
travels from one place to another
It's impossible for a hydrogen atom to emit an alpha particle
true
The radiation curve for a "blue hot" object peaks in the
ultraviolet region
The absorption of an infrared photon that excites an atom to emit a green photon
violates the law of energy conservation
quantization of electron energy states in an atom is better understood in terms of the electron's
wave nature
when Rutherford has a stream of alpha particles hit a gold foil, most of the particles
went almost straight through
If the radiation curve for an incandescent object peaks in the green region, the object would appear
white