# Physics Bushong

 Structures that absorb X-rays Radiopaque(ie. bone) Structures that transmit X-rays Radiolucent(ie. soft tissue) The Inverse Square Law can be applied to distances greater than _________ times the longest dimension of the source The inverse square law can be applied to distances greater than  SEVEN times the longest dimension of the source. States that the intensity of radiation at a location is inversely proportional to the square of its distance from the source. The Inverse Square Law A discrete bundle of energy the x-ray photon Photon energy is directly proportional to photon frequency Photon energy is ____________ proportional to photon wavelength Photon energy is INVERSELY proportional to photon wavelength. X-rays exist: at the speed of light or not at all E=hf Planck's Quantum Equation The longer the wavelength, the _____________ the energy of each photon. Lower(longer=lower) The law of conservation of mass & energy states: Energy & Matter can neither be destroyed or created The properties of elctromagnetic radiation include: (4) frequencywavelengthvelocityamplitude Electromagnetic energy exists over a wide range called: an energy continuum A continuum is an uninterrupted (continuous) ordered sequence. An atom of light Photon The smallest quantity of any type of electromagnetic energy photon A photon may be pictured as a small bundle of energy, sometimes called a Quantum A quantum of electromagnetic energy an x-ray photon Energy disturbances that move through space at the speed of light photon Mass of a photon Photons have NO MASSbut they do have electric and magnetic fields Speed of light 3x108 m/sThe speed of light (c) The velocity of electromagnetic radiation 3 x 108 m/s Variations of amplitude over time Sine wave One-half the range from crest to valley over which the sine wave varies Amplitude The number of wavelengths that pass a point of observation per second Frequency (f)measured in Hertz (Hz) The rate of rise and fall Frequency (f) What is frequency measured in? Hertz (Hz)One hertz is equal to one cylce per secondie. 20 cycles in 10 sec is 2 Hz The distance from one crest to another, one valley to another or from any point on the sine wave to the next corresponding point Wavelength What are the 3 parameters needed to describe electromagnetic energy? Velocity (v- measured in m/s)Frequency (f- measured in Hz)Wavelength At a given velocity _______________ & ______________ are inversely proportional wavelength & frequency For electromagnetic energy, frequency and ____________ are inversely proportional wavelength The deviation of course that occurs when photons of visible light traveling in straight lines pass from one transparent medium to another Refraction ________ light consists of photons with wavelengths longer than visible light but shorter than microwaves Infrared light ___________ light is between visible light & ionizing radiation on the spectrum Ultraviolet light An x-ray photon contains ___________ energy than a visible light photon or an RF photon considerably more The frequency of x-radiation is much _________ and the wavelength is much _________ than for other types of electromagnetic energy Higher (frequency)Shorter (wavelength) Where are x-rays produced? Outside of the nucleus of excited atoms; emitted from the electron cloud Where are gamma rays produced? Inside the nucleus of the atom A photon of x-radiation & a photon of visible light are fundamentally the same except that x-radiation has ________ frequency & hence a _________ wavelength Higher (frequncy)Shorter (wavelength) X-rays are identified by Energy Visible light tends to behave more like Waves X-ray photons tend to behave more like Particles The reduction in intesnsity that results from scattering and absorption Attenuation Transfer of energy from an electromagnetic field to matter. Removal of x-rays from a beam via the photoelectric effect. Absorption Return or re-entry of an x-ray Reflection Passage of an x-ray beam through an anatomical part with no interaction with anatomical structures Transmission AuthorRadiationTherapy ID180108 Card SetPhysics Bushong DescriptionRadiation Physics Test 10/29 Updated2014-01-03T21:05:38Z Show Answers