- 20.The __ functions to dissipate the heat away from the tungsten target. a. Copper stem b Transformer c. Molybdenum Cup d. A8B e. All of the above A B C D 21. The __ focuses the electrons into a narrow beam 8 directs the beam across the tube towards the anode. a. Tungsten filament b. Copper stem c. Molybdenum cup d. Tungsten target A B C D
- 17. The __ filters out the nonpenetrating, longer wavelength x-rays. a. Aluminum disks b. Lead collimator c. Cathode d. Anode A B C D 18. The __ or negative electrode consists of a tungsten wire filament. a. Anode b. Cathode A B 19. The tungsten target & copper stem is part of the __ a. Anode b. Cathode A B
- 13. Approximately what percentage of the kinetic energy of the electrons is converted to x-rays at the anode? a. Less than 1% b. 25% C. 50% d. 100% A B C D 14. Which form of the x-ray beam is most detrimental to the patient and operator? a. Primary radiation b. Secondary radiation C. Scatter radiation d. Useful beam A B C D
- While researching a topic.a student has taken the following notes: The Mpemba effect is the observation that, under certain conditions, warmer water can freeze faster than colder water. The effect is named after Erasto Mpemba, a Tanzanian student who observed it in 1963 while making ice cream. The Mpemba effect appears to contradict the laws of thermodynamics. as a hotter liquid would be expected to take longer to freeze than a colder liquid. Various mechanisms have been proposed to explain the Mpemba effect, including convection , evaporation, and supercooling. Despite numerous experimental observations and theories, the Mpemba effect remains poorly understood. The student wants to emphasize the puzzling nature of the Mpemba effect. Which choice most effectively uses relevant information from the notes to accomplish this goal? Choose 1 answer: A The Mpemba effect, named after Tanzanian student Erasto Mpemba, is the phenomenon of warmer water freezing faster than colder water. B The Mpemba effect, which defies expectations based on the laws of thermodynamics, is still largely a mystery to scientists. C The laws of thermodynamics are still poorly understood, as illustrated by the confusing nature of the Mpemba effect. D The mechanisms of convection evaporation, and supercooling all seem to conflict with the Mpemba effect.
- 11. Which component of the tubehead aims and shapes the x-ray beam? a. Metal housing b. Tubehead seal c. Aluminum disks d. Position-indicating device A B C D 12. __ is the measurement of the number of electrons moving through a conductor. a. Alternating current b. Direct current c. Amperage d. Voltage A B C D
