# 1เลือกประเภทWhat is the typical source-axis distance for a Co-60 teletherapy machine?60 cm70 cm80 cm90 cm
# 2เลือกประเภทWhich of the following is NOT a component of a Co-60 teletherapy source machine?Radioactive sourcePatient supportGantry and standMicrowave generator
# 3เลือกประเภทWhat material is commonly used in the construction of the collimator for Co-60 machines?LeadAluminumSteelCopper
# 4เลือกประเภทWhich method is most commonly used to control the movement of the Co-60 source?Mercury shutterRotating wheelMoving jawsSource drawer
# 5เลือกประเภทIn linear accelerators, what is the purpose of the electron gun?To generate microwavesTo accelerate electronsTo emit electronsTo detect radiation
# 6เลือกประเภทWhat is the function of the bending magnet in a linear accelerator?To generate microwavesTo change the electron beam directionTo accelerate electronsTo measure dose
# 7เลือกประเภทWhat is the primary purpose of a flattening filter in beam collimation?To increase beam intensityTo spread the electron beamTo make the beam intensity uniformTo measure radiation dose
# 8เลือกประเภทWhat is the role of a dual ionization chamber in a beam monitoring system?To generate microwavesTo provide a backup for dose measurementTo accelerate electronsTo shield radiation
# 9เลือกประเภทIn what mode does a scattering foil operate in a linear accelerator?Electron modePhoton modeGamma modeNeutron mode
# 10เลือกประเภทWhat material is typically used for the multileaf collimator?AluminumLeadTungstenCopper