dont know main Flashcards
compton scattering
photon removes electron
re-emitted as longer wavelength
what do dielectrics do
increases permitivity which increases capcitance
lenzs law
direction of induced emf opposes charge which caused it
fuel rod
contains uranium nuclei which undergoes fission when a neutron is absorbed
free charged particle
any charge moving in a magnetic field will experience a force perpendicular to the direction of its velocity
A-scan
stationary transducer
only measures depth using time to reflect
control rod
absorbs neutrons, no fission
gamma ray scintillator
absorbs gamma photons and re-emits many visible photons
binding energy
energy required to split a nucleus into its constituent nucleons
attenuated
absorbed, reduced intensity
what is EMF
energy supplied to each unit charge
motor effect
current-carrying wire in a magnetic field will experience a force
faradays law
induced EMF is proportional to rate of change of flux linkage
simple generator
spinning coil in a magnetic field
electric potential
energy required to move a unit charge from infinity to a point
gamma ray photomultiplier tubes
concerts photons energy into electrical signal
moderator
slows neutrons down so they are able to be absorbed by uranium nuclei in another rod
PET process
positron rich substance is injected
positrons annihilate electrons
pair of photons are produced
photon pair is detected by detectors
point of origin is calculated
image produced
transducer
produces the ultrasound by applying a varied p.d. to an array of piezoelectric crystals. crystals vibrate, this is detected and an image is produced
what happens when two mediums have equal impedance
they’re acoustically matched, so no sound is reflected
B scan
multiple a-scans when moving sideways
2D image is produced
CAT process
rotating x-ray tube around patient
rays are detected by detectors
detectors build 2D cross section images
2 non invasive processes
x-ray, MRI
invasive process
surgery
coulombs law
force between two charge particles is proportional to the product of their charges and inversely proportional to the square of their separation
