Mosby Ch. 3 - Physics Flashcards
what is Avogadro’s number?
6.0028 x 10^23
zXa what does each symbol represent?
Z- the atomic number (number of protons or electrons)
A- the atomic mass (the sum of protons and neutrons)
what is the speed of light equal to?
3x10^8 m/sec
name the photon interaction: when high energy photons interact with the nucleas; this leads to the emission of one or more nucleons or nueutrons; energies greater than 10 MeV have the greatest probability
photodisintegration
name the photon interaction: when the photon bundle passes near an orbiting electron and sets it into motion; no energy is absorbed by the aton, just redirected; this is probable in high atomic nymber materials and low energy beams less than 10 KeV
coherent scatter
name the photon interaction: when a photon ejects one of the orbiting electrons. The entire energy of the photon is first absorbed by the atom and then transferredto the atomic eectron. Thi happens in the innermost shells. The ejected electron is called a photo-electron. When vacancy occurs, another electron drop in to fill the space and energy emitted is in the form of characterisitic x-rays or auger electrons. the higher the energyy, the greater the probability of this type of interaction
photoelectric effect
name the photon interaction: when a photon interacts with an electron as though it were a free electron. This happens in the outer shell. The encountered electron reveives some energy from the phton and is emitted at an angle from the atom. The photon, with reduced energy, is also scattered at an angle. There could be a direct hit where the electron will move out and foward and the photon will travel backward. The higher the energy, the smaller the probability of this time of interaction. This effect is independent of atomic number of the matierial
comptom effect
name the photon interaction: occurs when the photon energy is greater than 1.02 MeV. The photon interacts with the electromagnetic field of the nucleus and gives up all its energy in the process of creating a pair of particles consisting of an electron and positron. THe particles are emitted in the foward direction; porbability of this type of interaction increases with atomic number
pair production
the amount of energy present per unit of time per unit of area perpendiculat to the beam direction
intensity
the energy of the beam expressed in electron voltsor the absorbing potential or penertrating power of the beam expressed in half value layer of material
beam quality
intensity of the beam is reduced by two effects
beam divergence and attenuation
some photons or particles are unaffeted by the attenuator and pass through; the photons or particles passing through are referred to as
transmission
equation for transmission
transmission=final intensity/original intensity
same number of protons but different number of neutrons
isotopes
same bmber of neutrons but different number of protons
isotones
same number of nucleons but different nymber of protons
isobars
same number of protons and neutrons except in a different nuclear state
isomers
what are the tradition and Si for activity
traditional: curie
SI: becquerel
1 Ci = ________ dps
3.7x10^10
what is the average life equation?
T=1.44(T1/2)
or
T1/2/0.693
what is the difference between the electron and proton?
electrons are light, negatively charged; they can collide and interact with other particles.
Protons are heavy, positively charged particles; only interact with electrons
Type of nuclear decay include all of the following except:
a. alpha decay
b. neutron decay
c. beta decay
d. internal conversion
b. neutron decay
The types of nuclear decay include alpha, beta neg/pos, electron capture, internal conversion, fission, & fussion
a result of bombarding certain high atomic number nuclides with heavy neutrons; the nucleus splits into nuclei of a lower atomic number
fission
low mass nuclei are combined to produce one nucleus
fusion
occurs with the emission of gamma rays from the nucleus. In most transformations, the daugher nucleus loses energy immediately in the form of gamma radiaiton. orbiting electrons may bombard the nuceus and recive some energy from the nucleus. the energized electron may subsequently be ejected from the atom and travel away with an energy equal to the difference between the energy lost by the nucleus and the binding energy that held the electron
internal conversion
when one of the orbitial electrons in captured by the nucleus. transforming a proton or neutrino. The neutrino would be ejected from the nucleus and carry away excess energy. The captured electron leaves an empty space in a electron shell, which in turn will be filled by another orbiting electron causing a release of energy known as characteristic x-rays
electron capture
The positive side of the basic x-ray tube is known as the
anode
The ratio of x-ray to heat during x-ray production is
a. constant at 99% heat and 1% xray
b. constant at 90% heat and 10% xray
c. variable depending on the maximum energy of electrons traversing the tube
d. variable depending on the strength of the target
c. variable depending on the maximum energy of electrons traversing the tube
the radioactive decay of a radioiostope is characterized by its
a. secular equilibrium
b. decay constant
c. fraction decay rate
d. transient equilibrium
b. decay constant
an elastic collision is one in which:
a. the incoing electron gives all of its energy to the electron it encounters
b. the incoming electron shares its energy with the electron it encounters
c. the incoming electron is captured by the nucleus
d. the incoming electron takes the place of an ejected electron
a. the incoing electron gives all of its energy to the electron it encounters
the majority of the mass of the atom is derived from:
a. protons and electrons in the nucleus
b. protons and neutron in the nucleus
c. protons, neutrons, and electrons in the nucleus
d. alpha, beta, and gamma radiation emitted
b. protons and neutron in the nucleus
an atom is neutral if the number of electrons is equal to its
a. protons
b. nucleons
c. atomic weight
d. none of the above
a. protons
to interact by photoelectric effect, the interacting photon must have energy:
a. less than the binding energy of the orbiting electron
b. equal to or greater than the binding energy of the orbiting electron
c. of any level
d. of at least 1 MeV
b. equal to or greater than the binding energy of the orbiting electron
the photon produced during the orbital transitions of electrons from a higher to lower energy are called:
a. characterisitic radiation
b. corpuscular radiation
c. gamma radiation
d. vacancy radiation
a. characterisitic radiation
two or more chemicals with the same chemical formula, but having different nuclear states are known as:
a. isomers
b. isotopes
c. isobars
d. isotones
a. isomers
which is not true of the electromagnetic spectrum: they all have the same
a. velocity
b. energy
c. mass
d. charge
b. energy
carbon-12 and nitrogen-12 are:
a. isotones
b. isotopes
c. isobars
d. isomers
c. isobars
isobars have the same mass
