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equipment-DENH
Question | Answer |
---|---|
what is voltage? | force that drives electric current through circuit; affects contrast |
what is the basic unit of voltage? | volt = kilovolt |
what occurs if KVP(voltage) is increased? | voltage increase = increase speed = decrease size/wavelength = increase penetration |
what is ampere? | amount of electrical current flowing through circuit |
what is ampere determined by? | film speed, exposure time, and PID |
what and how is ampere controlled? | controls quantity and is controlled by MA |
What do transformers do? | increase (step-up) or decrease (step down) alternating current and voltage |
what is the difference between low and high voltage circuits? | low (step down) heats tube filament to incandescence and high (step up) activates electrons at heated filament toward anode(target) |
what is electromagnetic radiation? | wire moved through magnetic field, electrons in wire induced to flow |
are the wavelengths of x-rays mono or polychromatic? | polychromatic = waves of more than one frequency and wavelength |
what is intensity of x-ray affected by? | KVP, MA, exposure time and FFD |
what happens if MA and KVP are increased? | increases intensity |
increase in exposure time? | increases intensity |
increase FFD? | decreases intensity (due to divergent beam) |
what occurs as move AWAY from central ray? | divergency of x-rays increases |
what is the inverse square law? | intensity is less at increasing distances from source; as distance doubles, intensity quadruples = distance increase, intensity decrease |
what is electricity? | flow of electrons produced by electrical differences |
what is the difference between direct and alternating current? | direct-flows in one direction; alternating-flows in both directions |
what does KVP refer to? | kilovolt peak |
what are factors determine KVP? | object density or type of contrast desired |
THE "24" ON THE TIMER DIAL STANDS FOR? | 24 IMPULSES/SEC |
SCATTER RADIATION FROM PID IS PREVENTED BY? | LEAD LINING |
THE COMPONENT THAT AUTOMATICALY ADJUSTS FLUCTUATION IN VOLTAGE IS CALLED? | AUTOTRANSFORMER |
X-RAYS OF ____ WAVELENGTH ARE MOST LIKELY TO RESULT IN SECONDARY RADIATION? | LONG |