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The properties of ____ ____ include frequency, wavelength, velocity and amplitude.
electromagnetic energy
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Ever present around us is a field or state of energy called ___ ___ ?
electromagnetic energy
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Electromagnetic energy exist over a wide range called an
energy _____.
continuum
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A _____ is an uninterrupted (continuous) ordered sequence.
continuum
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An atom of light is called a ______ ?
photon
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A _____ is the smallest quantity of any type of electromagnetic energy, just as an atom is the smallest quanity of an element.
PHOTON
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A photon may be pictured as a small bundle of energy, sometimes called a _____, that travels through space at the speed of light
quantum
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We speak of x-ray photons, light photons, and other types of electromagnetic energy as _____ ______
photo radiation
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An x-ray photon is a quantum of electromagnetic energy
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late in the 19th century, James Clerk Maxwell showed that visible light has both electrical and magnetic properties, hence the term ___________ __________.
electromagnetic energy
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Photons are _____ _____ tht move through space at the spped of light (c)
energy disturbances
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The velocity of all electromagnetic radiation is 3 x 10 to the eighth m/s.
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The term _____ describes interactions among different energies, forces, or masses that can otherwise be described only mathematically.
field
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Amplitude is one- half the range from the creast to valley over which the sine waves varies.
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c represents _________
f represents__________
lambda symbol represents____________
velocity
frequency
wavelength
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The rate of rise & fall is ___________.
It is usually identified as cycles per second
frequency
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One _____ is equal to 1 cycle per second
hertz
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the _____ is equal to the number of crest or the number of valleys that pass the point of an observer per unit of time.
frequency
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frequency is the number of wavelengths that pass a point of observation per second.
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The _____ is the distance from one crest to another, from one valley to another, or from any point on the sine wave to the next corresponding point.
wavelength
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Three wave parameters - _____, _____, and _____ - are needed to describe electromagnetic energy.
The relationship among these parameters is important.
A change in one affects the value of the others.
Velocity is constant
velocity, frequency & wavelength
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At a given velocity, waveength and frequency are inversly proportional.
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The wave _____ is used for both sound & electromagnetic energy.
equation
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for electromagnetic energy, frequency and wavelength are inversly proportional.
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THe electromagnetic spectrum includes the entire range of electromagnetic energy.
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_____ is used to describe radio waves
hertz
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Diagnostic ultrasound is not part of the electromagnetic spectrum
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The known electromagnetic spectrum has three regions most important to radiologic science: ___ ____, and ___.
Other portions of the spectrum include ultraviolet light, infared light, and microwave radiation.
visible light, x and gamma ray, and RF
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The energy of a photon is directly proportional to its frequency
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This deviation in line of travel, called _____, is the cause of many peculiar but familar phenomena, such as a rainbow or the apparent bending of a straw in a glass of water.
refraction
-
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Communication broadcast are usually identified by their frequency of transmission and are called _______ emissions.
radiofrequency (RF)
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A very short wavelength RF is _______ radiation.
microwave
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An _____ photon contains considerably more energy than a visible light photon or an RF photon
x-ray
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It is sometime said that ___ ____ have higher energy than x-rays
gamma rays
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The only difference between xrays and gamma rays is their origin
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______ are emitted from the electron cloud of an atom that has been stimulated artifically.
x rays
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____ ____, come from inside the nucleus of a radioactive atom
gamma rays
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Visible light is identified by wavelength, radiofrequency is identified by frequency, and x-rays are identified by energy.
-
x- rays are produced outside the nucleus of excited atoms
-
Gamma rays are produced inside the nucleus of radioactive atoms
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Note: A photon od x-radiation and a photonof visible light are fundamentally the same except that x-radiation has a much higher freqency,a nd hence a shorter wavelength, than visible light. These differences result in differences in the way these photons interact with matter.
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___ -____ photons tend to behave more like waves than particles
Visible - light
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__-___ behave more liek particles than waves
x-rays
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In fact, both types of photons exhibits both types of behavior - a phenomenon known as the ___-___ ____ of electromagnetic energy
wave particle duality
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Photons interact with matter most easily when the matter is approximately the same size as the photon wavelength
-
x-rays behave as though they are particles
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the ____-_____ spectrum extends from short-wavelength violet radiation through green and yellow to long wavelength red radiation.
visible light
-
visible light behaves like a wave
-
Electromagnetic energy attenuation is the reduction in intensity that results from scattering and absorption
-
Instead of seeing clearly through the glass, it is blurred.
this glass is known as
translucent
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The terms ____ and _____ are sed routinely in x-ray diagnosis to describe the visual appearance of anatomical structures
radioplaque & radiolucent
-
Structures that absorb x-rays are called
radiopaque
Bone is radioplaque - lung tissue is radiolucent
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Structures that transmits x-rays are called ______
radiolucent
lung tissue is radiolucent - bone is radioplque
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The decrease in intensity is inversely proportional to the square of the distance of the object from the source is known as the:
Inverse Square law
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Electromagnetic energy (radation) intensity is inversely related to the square of distance from the source
-
The inverse square law canbe applied to distances greater than seventimes the longest dimesion of the source
-
To appply the inverse square law you must know 3 of the 4 parameters, which consist on two ______ and two _____.
distances & intensities
-
The x-ray photon is a discrete bundle of energy
-
Xrays exist with the speed of light (c), and they exist with velocity (c) or they do not exist at all.
That is one of the substansive statements of _____ _____ _____.
Planck's quantum theory
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Another important consequence of the quantum theory is the relationship between _____ and _____
energy & frequency
-
Photon energy is directly proportional to photon frequency
-
The constant of proportionality, knwon as ____ ____ and is symbolized by (h)
Planck's constant
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The energy of a photon is directly proportional to its frequency
-
According to classic physics, matter can be neither created nor destroyed, a law known as the
law of conservation matter
-
This law states that energy can neither be created nor destroyed
law of conservation of energy
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_____ _____ is an example of the conversion of energy into mass
pair production
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A ____ is a unit of energy
joule
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Summary: Although matter and energy are interchangable, x-ray imaging is based on energy in the form of x-ray photons that interact with tissue and an image receptor.
x-rays are one type of photon of electromagnetic energy. Frequency, wavelength, velocity, and amplitude are used to describe the various imaging regions of the elecromagnetic spectrum. These characterics of electromagnetic energy determine how such radiation interacts with matter
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