Principles of Radiation Physics Exam Questions
With Correct Answers 100% Verified.
X-ray Production-What's needed - Answer✔1. Source of Free Electrons
2. Acceleration of Electrons
3. Focusing of Electrons
4. Deceleration of Electrons
Source of Free Electrons - Answer✔Thermionic Emission
-Electrons are released from the surface of one or two filament wires by a process called
thermionic emission
-While current passes through the wire, heat causes the separation of electrons that will be
released from the wire
Acceleration of Electrons - Answer✔Free electrons must be accelerated across the x-ray tube
from cathode to anode
kVp forces the electrons across the tube giving them kinetic energy; the higher the kVp the
more energy the electrons will have
Focusing of Electrons - Answer✔-Focusing cup houses the filament wire
-Cup holds the electrons around the wire in a cloud (space charge) until the exposure switch is
activated; when the kVp is applied, the electrons are focused into a narrow beam directed
toward the anode
Deceleration of Electrons - Answer✔Electrons decelerate when they strike the anode.
Anode is a tungsten disk with a high atomic number and high melting point
Target Interaction - Answer✔-X-rays are produced by one of these methods when electrons
interact with the anode
-Bremsstrahlung
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