Ch 3 Electromagnetic Energy Flashcards
the properties of electromagnetic energy are:
frequency, wavelength, velocity & amplitude
*A photon is the smallest quantity of ____
any type of electromagnetic energy
quantum is:
a small bundle of energy
photon have __amu
0 amu (no mass)
*velocity of all electromagnetic radiation is:
3x10^8 m/s
*AMPLITUDE is ___
one half the range from crest to valley over which the sine wave varies, how high or low it is, tells you the peak of kVp
*FREQUENCY is ___
the number of wavelength that pass a point per second, (rate of rise to fall), measurement is hertz (Hz)
1 Hz =
1 cycle per second
*WAVELENGTH is ____
the distance from one point to the next corresponding point on a sine wave, from crest to crest or valley to valley
3 wave parameters are:
velocity (constant), frequency, wavelength
*At any given velocity, frequency and wavelength are:
inversely proportional
*Diagnostic ultrasound is___
not part of the electromagnetic spectrum
visible light is described by___ and measured in __
wavelength, nanometers (nm)
*The energy of a photon is:
directly proportional to its frequency
refraction:
the deviation in a line of travel
the colors of white light:
have varying wavelengths ranging from 400nm for violet to 700nm for red
infrared light:
heats any substance that is shines on, is considered radiant heat
ultraviolet light:
causes molecular interactions that can cause sunburn
RF has:
relatively low energy and long wavelengths
*visible light is identified by ___
radio frequency is identified by ___
x-rays are identified by ___
wavelength
frequency
energy
*Photons interact with matter most easily:
when the matter is approximately the same size as the photons wavelength
visible light interacts with:
living cells (roads & cones)
ultraviolet light interacts with:
molecules
x-rays interact with:
electrons and atoms
*X-rays behave as though they are:
particles
*visible light behaves like a:
wave
*electromagnetic energy attenuation is the:
reduction of intensity that results from scatter and absorption (attenuation=scatter+absorption)
when light waves are absorbed, the energy absorber reappears as:
heat
transparent:
light is transmitted almost unaltered
translucent:
light is still transmitted but greatly scattered and reducesd in intensity, blurred
opaque:
light is totally absorbed
*electromagnetic energy intensity is:
inversely related to the square of the distance from the source
*the inverse square law can be applied to distances:
greater than 7 times the longest dimension of the source
*photon energy is _____ to the photon frequency
directly proportional
the longer the wavelength of electromagnetic energy, the:
lower the energy of each photon
energy absorbed that is not ionized becomes:
heat
if amplitude goes up, frequency ____
goes down
energy and frequency are:
proportional
the kVp range of diagnostic x-rays is:
30-150 kVp
the only units of energy are:
eV, J & erg
frequency and wavelength are:
inversely proportional
with electromagnetic radiation, the _____ field and the _____ field are _______
electric, magnetic, perpendicular sine waves
