Physics Test
How many neutrons does Th-228 have
138
Light behaves as a
Particle and Wave
What makes an element distinct?
The number of protons
The type of radiation that will penetrate farthest into a material is
a gamma ray
A photocell can be activated with blue light but not with red light. This is because blue light has
a higher frequency than red light.
Which type of radioactive decay occurs when the atomic number increases by one?
beta decay
If two protons are removed from an oxygen nucleus, the result is _____.
carbon
When a nucleus emits a beta particle, its atomic number
changes, but its mass number remains constant.
Energy released by the sun results from atomic nuclei
combining
Nuclear fission occurs when
electrical forces inside a nucleus overpower nuclear forces.
When light shines on a photosensitive material
electrons may be ejected.
The energy of a photon is directly proportional to its
frequency
The number of electrons ejected in the photoelectric effect depends on the light beam's
frequency
Which radiation has no electric charge associated with it?
gamma rays
All elements beyond uranium in the periodic table
have no isotopes
Large nuclei like uranium are radioactive because
none of the above
When thorium (90 protons) ejects a beta particle, the resulting nucleus has
none of the above
The atomic mass number of an atom refers to the number of
nucleons
At the center of every atom is a mass-filled region called the _____.
nucleus
In the photoelectric effect, the brighter the illuminating light on a photosensitive surface, the greater the
number of ejected electrons.
Isotopes are atoms of the same element that have a different
number of neutrons
The photoelectric effect best demonstrates the
particle nature of light
The nucleus of an atom consists of
protons and neutrons.
The atomic number of an atom or ion refers to the number of
protons.
Electrical forces within an atomic nucleus tend to
push it apart
The energy states available to an electron are
quantized.
The force that holds the nucleus together is the
strong force.
Nuclear fusion occurs typically in
the sun.
When U-235 splits, it usually emits
three neutrons
An alpha particle consists of
two protons and two neutrons.
Which of the following photons have the greatest energy?
ultraviolet
Generally speaking, the heavier a nucleus is, the more it is
unstable.
The primary fuel for a nuclear fusion reactor is
uranium.
Nuclear fusion releases energy when
very light nuclei fuse together.