Dental Radiography Final Exam Review

The x-ray was discovered on November 8, 1895, by:   

• a. John Greenwood
• b. Wilhelm Conrad Roentgen.
• c. Edmund Kells.
• d. G.V. Black.

Which of the following statements is true concerning the structure of the atom?        

• a. The nucleus contains protons and electrons.
• b. Electrons have no weight or mass.
• c.The orbital path of an electron around the nucleus is called an electron shell.
• d. Electrons are unstable in their orbits and shift freely.

In dentistry, the _____ the wavelengths of the x-rays, the greater their energy and their usefulness. 

• shorter
• longer
• more ionized
• straighter

Secondary radiation:  

• a. is often referred to as the useful beam.
• b. is often referred to as the primary beam.
• c. refers to x-radiation that is created when the primary beam interacts with matter.
• d. is a form of radiation that occurs when an x-ray beam has been deflected from its path by interaction with matter.

All the following are true of electromagnetic radiation except they:   

• a. are composed of photons that travel through space in waveforms.
• b. travel at various speeds.
• c. differ only by their wavelength.
• d. travel in straight lines.

The portion of the x-ray machine that supplies the electrons to produce x-rays is the: 

• cathode
• anode
• control panel
• focusing cup

The penetrating power of the x-ray beam is controlled by the settings on the: 

• impulse timer
• kilovolt setting
• milliamp setting
• All are correct

An example of cumulative radiation exposure is: a. cataracts. b. leukemia. c. cancer. d. all of the above.

• cataracts
• leukemia
• cancer
• all of the above

The location where x-rays are produced in the x-ray tube is called the: a. focal spot. b. filament. c. window. d. PID.

• focal spot
• filament
• window
• PID

When the electrons slam against the target, _______ are generated.  

• a. 99% heat and 1% x-rays
• b. 1% heat and 99% x-rays
• c. 50% x-rays and 50% heat
• d. only x-rays