physics final Flashcards
binding energies are measured in …….
binding energy is…
electron volts.
The energy it takes to remove an electron from its shell
The atomic number, or Z # and the number of _________is the same.
protons
what is the binding energy of a tungsten K shell electron?
69.5
what type of current does the x-ray TUBE use?
DC
A step up transformer converts volts to_______
kilovolts
diode rectifiers in an x-ray circuit convert _________current to _______current.
AC to dc
where are x-rays produced?
at the actual focal spot
when high-speed electrons from the filament in the tube crossto the anode what type of radiation is being created?
primary
what are the two types of primary radiation?
Brems and characteristic
The majority of the emission spectrum is made up of what type of radiation?
brems
The tube housing and glass window of the x-ray to our considered ________ _________.
inherent filtration
The reflective mirror in the x-ray tube is considered ________ filtration
added
what two types of Filtration = total filtration?
inherent, added
what is the line focus principal used for?
to dissipate heat and increase detail
when the target is angled less than 45° which focal spot is smaller?
effective.
The actual focal spot is larger
the Octet rule states:
The outermost shell of an Atom never exceeds 8 electrons
The periodic table is based upon ______ ______.
atomic number
photon wavelength is inversely or directly proportional to photon frequency?
inversely
what are the two theories that x-rays might be described as
wave theory and particle theory
electromagnetic radiation has properties of
waves and particles
in wave theory, Frequency and wavelength are _______proportional
inversely
what particles distinguish one element from another?
protons
what is the wave equation?
V= F X W
Velocity equals frequency times wavelength
what are three properties of x-rays?
they can ionize matter, cannot be focused, cause florescence of certain crystals
Electric potential difference is measured in ________
volts
the mA is a unit of ______
current
mass is the quantity of _____
matter
is binding energy increased or decreased as it gets closer to the nucleus?
increased
what is the smallest particle of an element?
atom
two or more atoms chemically united equal _____
a molecule
in simple terms describe theory of relativity
matter and energy are interchangeable
protons and neutrons are composed of even smaller structures called ________
quarks
if an atom gains or loses neutrons it is called an_____
isotope
what are the two types of mechanical energy
potential and kinetic
x-rays are a form of man-made electromagnetic energy that is created in the tube when high-speed electrons electronics are ______ _______
suddenly stopped
for electromagnetic radiation to be capable of ionization they must have an energy higher than
10 electron volts
electromagnetic radiation can transfer energy to an atom by…
excitation
describe excitation
electrons in and Atom are moved to a higher energy state without actually being removed from the Atom
in what way are electromagnetic waves unique?
no medium is needed they travel in a vacuum
the INTENSITY of the wave is defined by its maximum height measured in…._______
Amps (amplitude)
who invented the motor?
orsted
what are the 5 laws of electrostatics?
repulsion-attraction
inverse square law
distribution
concentration
movement
objects can be electrified by 3 methods:
friction
contact
induction
what type of current do transformers use?
AC
the QUANTITY of electrons flowing is called the ______
current
current is measured in _____
amps
what is the unit to measure resistance?
Ohms
what are the 4 primary factors for electrical circuits?
ability to conduct electrons
length of the conductor
cross sectional diameter
temperature
ohms law
resistance ( ohms) X current (amps) (I) = potential difference (volts).
Who discovered that an electric current flowing through a wire could affect a Compass
oersted
faradays experiment proved that a current could be induced by a magnetic field only :
if the field is changing
A magnet created by a coil of wire is called a
solenoid
The magnitude of an induced current depends on what three things?
angle of the conductor, number of turns in the conductor, velocity of the magnetic field as it moves past the conductor
true or false:
transformer converts electrical potential to higher or lower intensity
true
magnetic lines of force are also referred to as _____ ____
flux lines
and AC generator produces current that is mathematically expressed as a ______wave.
sinusoidal
what type of motor uses slip rings?
AC
List three ways to create current in a circuit
move the wire, move the conductor, Vary the flux lines
what three factors control how effective solenoids and electromagnets are
diameter of the coil, length of the coil, current passing along the coil
what three things determine the strength of solenoids and electromagnets?
Number of loops or turns of the wire, the current strengths, permeability of the core
what four factors regulate the strength of induced current
strengths of the magnetic field
speed of the motion between lines of force and the conductor
angle between the magnetic lines of force and the conductor
and the number of turns in the coil
what law supports self induction
lenzs law
A device capable of accumulating and storing the electrical charge
capacitors
