RADT 100 Exam 1 Questions and Answers 2026

RADT 100 Exam 1 Questions and Answers 2026/2027

1. · When and who discovered x rays, fluoroscopy: o Wilhelm Conrad Roentgen: x-rays o Thomas Edison: invented first fluoroscope 2. · Review the characteristics of xrays: o Cannot be refracted by a lens o Not detectable by human senses o Can ionize matter o Travel in straight lines o Can penetrate matter that is opaque to light o Causes certain crystals to flow (fluoresce) 3. · Review the parts of the xray machine and xray tube: anode cathode filaments focusing cup target anode stator 4. · What grids or buckys are used for and when are they used?: o Grids and buckys: put between patient and IR to prevent scatter radiation from degrading the image 5. · What departments use ionizing radiation: - X-Rays - Radiation Therapy - Mammogram - CT Scan - Pet Scan - Nuclear Medicine - Therapeutic X-Ray - Gamma rays - Diagnostic X-Rays 6. · How do we calculate mAs?: o mA and exposure time (mAs when combined) affect the quantity only 7. · What is an intensifying screen, when and why do we use them?: converts the x-ray energy into light, which reaches the film and forms the latent image 8. · Know what mAs does vs. kVp and which combination of mAs and kVp results in the lowest patient dose: An increase in kVp results in a more penetrating x-ray beam. More exposure to the IR An increase in kVp will make a darker image A decrease in kVp will make a lighter image 9. · Magnification: enlargement 10. size distortion: Size distortion Magnification SID and OID affect it Increased SID and decreased OID= less magnification 11. OID: object to image distance 12. SID: SID: distance between x-ray beam and the IR 13. shape distortion: Unequal magnification of the parts of the subject Misalignment of the body part Misalignment of the IR Misalignment of the x-ray tube 14. · Define rad, rem, Sv, Gy.Which are traditional (British) units and which are SI (Standard International) units?: rad: 1 rad unit in traditional British system to measure patient dose radiation absorbed dose rem: equivalent dose British Sv: unit in SI to measure dose equivalents Gy: unit in SI to measure patient dose 15. · Know what the conversion or equivalent from rad to Gy is: - 1 rad= .01 Gy 16. · Know that the conversion or equivalent from rem to Sv is: - 1 rem = .01 Sv 17. · Define Roentgen (R): measurement of the intensity of radiation exposure in air. british system 18. · ALARA: As Low As Reasonably Achievable 19. · Radiation safety rules: - Minimize Exposure Time - Maximize Distance - Use Shielding - Wear Dosimeters