LRA 211 Final Review Study Guide (223/2024) Graded A+

LRA 211 Final Review Study Guide (223/2024) Graded A+ The earliest atomic theory based on an arrangement similar to the solar system is attributed to Rutherford. The three fundamental particles of the atom are the neutron, electron, and proton. The atomic nucleus contains protons and neutrons. The component of the nucleus that has a positive charge and mass is the proton. The electron shell closest to the nucleus is lettered "K". Which of the following is not part of the electromagnetic spectrum? Sound Which of the following electromagnetic radiations have the lowest energy level? Radio waves As the wave's frequency increases, the wavelength decreases. Frequency is typically measured in hertz. The process of removing an electron from an atom is ionization. X-rays are produced using fast-moving electrons. Which of the following helps to keep the x-ray tube cool on the inside of the protective housing? Cooling fans and an oil bath In terms of the x-ray tube, envelope is another name for the glass or metal enclosure. The positive end of the x-ray tube is the anode. The negative end of the x-ray tube is the cathode. The area of the envelope where x-rays should exit the tube is the target window. The anode serves as a(n) target for the electron interaction to produce x-ray, electrical conductor, heat conductor. The two types of anode designs are stationary and rotating. Tungsten is used to coat the anode disc because it has a high atomic number. With a rotating anode, the focal spot becomes a focal track. X-rays are produced by characteristic and bremsstrahlung interactions. When filament electrons enter the anode target, they interact with outer shell electrons of tungsten atoms. When a filament electron knocks out a K shell electron from the tungsten atom, it leads to a characteristic x-ray photon. The energy of the characteristic x-ray photon depends on the binding energy of the inner-shell electron the energy level of the filament electron the shell of the electron that is dropping into the vacancy. A filament electron removes a K shell electron and an M shell electron fills the vacancy. The K shell binding energy is 69.5 keV and the M shell binding energy is 2.8 keV. What is the energy of the K-characteristic photon produced? 66.7 keV Bremsstrahlung means braking radiation. The energy of the brems photon depends on the original energy of the filament electron the strength of the attraction between the electron and the nucleus the energy of the filament electron as it leaves the tungsten atom. The majority of the x-ray photons produced are brems photons. Which of the following is the primary factor controlling quantity? mAs As the distance increases, the beam quantity reaching a specific area decreases. Classical interactions are also known as Thomson and coherent scattering. Coherent scattering involves an x-ray photon with low energy. With Compton scattering, the incident photon loses up to one third of its energy. Secondary photons produced during a Compton interaction contribute to patient dose. When it does interact with the image receptor, the Compton scatter photon contributes no useful information because it has changed direction. The fog seen on the radiographic image is the result of Compton interactions. The primary source of radiation exposure to the radiographer who is in the room during an exposure is from scatter from the patient. To minimize occupational exposure, the technologist should wear protective apparel (lead aprons, gloves, etc.) when in the room during imaging. Photoelectric interactions contribute significantly to patient dose. Radiation interacting with air is more likely to be _____________, resulting in that area of the image being darker. Transmitted The device that receives the radiation after it exits the patient is the Image receptor. Which of the following is an example of an image receptor? Film-screen and digital In producing a radiographic image, which of the following occurs first? Quality and quantity of x-ray beam exit the x-ray tube In producing a radiographic image, which of the following occurs last? Radiation interacts with image receptor The latent image that is formed on the image receptor is the invisible image. Complete absorption of the diagnostic range x-ray photon is the interaction known as photoelectric interaction. The photoelectric interaction involves removal of an inner-shell electron. The ability to remove electrons from an atom is ionization. The probability of a Compton interaction is _______________ in bone than soft tissue. the same Transmission refers to x-rays leaving the patient that did not interact with atoms. The overall quality of the radiographic image is determined by sharpness visibility of anatomic structures accuracy of structural lines. The amount of light emitted from the display monitor is brightness. A radiographic image that is too light has ________________ to visualize the anatomic structures. excessive brightness If there were no contrast, the radiographic image would include only the same shade of gray. Which of the following contribute to subject contrast? Differences in tissue thickness Differences in tissue density Effective atomic number Resolution is typically measured in line pairs per millimeter. The radiographic misrepresentation of either the size (magnification) or the shape of the anatomic part is called distortion. An increase in the image size of an object compared with its true, or actual, size, is called size distortion. Size distortion is also called magnification. Scatter radiation decreases the visibility of anatomic structures.