,CHAPTER 1: Radiation History
PART I: MULTIPLE CHOICE
Question 1: Radiation is defined as:
A) A form of energy carried by waves or streams of particles
B) A beam of energy that has the power to penetrate substances and record image shadows on a
receptor
C) A high-energy radiation produced by the collision of a beam of electrons with a metal target in an x-
ray tube
D) A branch of medicine that deals with the use of x-rays
ANS: A
Rationale: Radiation is a form of energy carried by waves or streams of particles .
Question 2: A radiograph is defined as:
A) A beam of energy that has the power to penetrate substances and record image shadows on a
receptor
B) A picture on film produced by the passage of x-rays through an object or body
C) The art and science of making radiographs by the exposure of an image receptor to x-rays
D) A form of energy carried by waves or a stream of particles
ANS: B
Rationale: A radiograph is a picture on film produced by the passage of x-rays through an object or body
.
Question 3: Your patient asks you why dental images are important. Which of the following is the
correct response?
A) An oral examination with dental images limits the practitioner to what is seen clinically
B) All dental diseases and conditions produce clinical signs and symptoms
C) Dental images are not a necessary component of comprehensive patient care
D) Many dental diseases are typically discovered only through the use of dental images
ANS: D
Rationale: Many dental diseases are typically discovered only through the use of dental images .
Question 4: The x-ray was discovered by:
A) Heinrich Geissler
B) Wilhelm Roentgen
C) Johann Hittorf
D) William Crookes
ANS: B
Rationale: Wilhelm Roentgen discovered the x-ray on November 8, 1895 .
Question 5: Who exposed the first dental radiograph in the United States using a live person?
A) Otto Walkoff
B) Wilhelm Roentgen
C) Edmund Kells
,D) Weston Price
ANS: C
Rationale: Edmund Kells exposed the first dental radiograph in the United States using a live person .
Question 6: Current fast radiographic film requires what percentage less exposure time than the initial
exposure times used in 1920?
A) 33%
B) 98%
C) 73%
D) 2%
ANS: B
Rationale: Current fast radiographic film requires 98% less exposure time than the initial exposure times
used in 1920 .
Question 7: Who modified the paralleling technique with the introduction of the long-cone technique?
A) C. Edmund Kells
B) Franklin W. McCormack
C) F. Gordon Fitzgerald
D) Howard Riley Raper
ANS: C
Rationale: F. Gordon Fitzgerald modified the paralleling technique with the introduction of the long-
cone technique .
Question 8: Which discovery was the precursor to the discovery of x-rays?
A) Beta particles
B) Alpha particles
C) Cathode rays
D) Radioactive materials
ANS: C
Rationale: Wilhelm Roentgen was experimenting with cathode rays when he discovered x-rays .
Question 9: Which of the following would you place in the patient's mouth in order to take dental x-
rays?
A) Image
B) Image receptor
C) Radiograph
D) X-ray
ANS: B
Rationale: An image receptor is the recording medium (film, phosphor plate, or digital sensor) placed in
the patient's mouth to record the image produced by the x-rays .
Question 10: Who was the German dentist who made the first dental radiograph?
A) Otto Walkoff
B) Wilhelm Roentgen
C) Edmund Kells
D) Weston Price
, ANS: A
Rationale: Otto Walkoff was a German dentist who made the first dental radiograph .
Question 11: Who introduced the bisecting technique in 1904?
A) Otto Walkoff
B) Wilhelm Roentgen
C) Edmund Kells
D) Weston Price
ANS: D
Rationale: Weston Price introduced the bisecting technique in 1904 .
Question 12: Who built the first vacuum tube in 1838?
A) Heinrich Geissler
B) Wilhelm Roentgen
C) Johann Hittorf
D) William Crookes
ANS: A
Rationale: Heinrich Geissler built the first vacuum tube in 1838 .
Question 13: Who observed in 1870 that discharges emitted from the negative electrode of a vacuum
tube traveled in straight lines?
A) Heinrich Geissler
B) Wilhelm Roentgen
C) Johann Hittorf
D) William Crookes
ANS: C
Rationale: Johann Hittorf observed in 1870 that discharges emitted from the negative electrode of a
vacuum tube traveled in straight lines .
Question 14: Who discovered in the late 1870s that cathode rays were streams of charged particles?
A) Heinrich Geissler
B) Wilhelm Roentgen
C) Johann Hittorf
D) William Crookes
ANS: D
Rationale: William Crookes discovered in the late 1870s that cathode rays were streams of charged
particles .
Question 15: Who introduced the paralleling technique in 1896?
A) C. Edmund Kells
B) Franklin W. McCormack
C) F. Gordon Fitzgerald
D) Howard Riley Raper
ANS: A
Rationale: C. Edmund Kells introduced the paralleling technique in 1896 .
PART I: MULTIPLE CHOICE
Question 1: Radiation is defined as:
A) A form of energy carried by waves or streams of particles
B) A beam of energy that has the power to penetrate substances and record image shadows on a
receptor
C) A high-energy radiation produced by the collision of a beam of electrons with a metal target in an x-
ray tube
D) A branch of medicine that deals with the use of x-rays
ANS: A
Rationale: Radiation is a form of energy carried by waves or streams of particles .
Question 2: A radiograph is defined as:
A) A beam of energy that has the power to penetrate substances and record image shadows on a
receptor
B) A picture on film produced by the passage of x-rays through an object or body
C) The art and science of making radiographs by the exposure of an image receptor to x-rays
D) A form of energy carried by waves or a stream of particles
ANS: B
Rationale: A radiograph is a picture on film produced by the passage of x-rays through an object or body
.
Question 3: Your patient asks you why dental images are important. Which of the following is the
correct response?
A) An oral examination with dental images limits the practitioner to what is seen clinically
B) All dental diseases and conditions produce clinical signs and symptoms
C) Dental images are not a necessary component of comprehensive patient care
D) Many dental diseases are typically discovered only through the use of dental images
ANS: D
Rationale: Many dental diseases are typically discovered only through the use of dental images .
Question 4: The x-ray was discovered by:
A) Heinrich Geissler
B) Wilhelm Roentgen
C) Johann Hittorf
D) William Crookes
ANS: B
Rationale: Wilhelm Roentgen discovered the x-ray on November 8, 1895 .
Question 5: Who exposed the first dental radiograph in the United States using a live person?
A) Otto Walkoff
B) Wilhelm Roentgen
C) Edmund Kells
,D) Weston Price
ANS: C
Rationale: Edmund Kells exposed the first dental radiograph in the United States using a live person .
Question 6: Current fast radiographic film requires what percentage less exposure time than the initial
exposure times used in 1920?
A) 33%
B) 98%
C) 73%
D) 2%
ANS: B
Rationale: Current fast radiographic film requires 98% less exposure time than the initial exposure times
used in 1920 .
Question 7: Who modified the paralleling technique with the introduction of the long-cone technique?
A) C. Edmund Kells
B) Franklin W. McCormack
C) F. Gordon Fitzgerald
D) Howard Riley Raper
ANS: C
Rationale: F. Gordon Fitzgerald modified the paralleling technique with the introduction of the long-
cone technique .
Question 8: Which discovery was the precursor to the discovery of x-rays?
A) Beta particles
B) Alpha particles
C) Cathode rays
D) Radioactive materials
ANS: C
Rationale: Wilhelm Roentgen was experimenting with cathode rays when he discovered x-rays .
Question 9: Which of the following would you place in the patient's mouth in order to take dental x-
rays?
A) Image
B) Image receptor
C) Radiograph
D) X-ray
ANS: B
Rationale: An image receptor is the recording medium (film, phosphor plate, or digital sensor) placed in
the patient's mouth to record the image produced by the x-rays .
Question 10: Who was the German dentist who made the first dental radiograph?
A) Otto Walkoff
B) Wilhelm Roentgen
C) Edmund Kells
D) Weston Price
, ANS: A
Rationale: Otto Walkoff was a German dentist who made the first dental radiograph .
Question 11: Who introduced the bisecting technique in 1904?
A) Otto Walkoff
B) Wilhelm Roentgen
C) Edmund Kells
D) Weston Price
ANS: D
Rationale: Weston Price introduced the bisecting technique in 1904 .
Question 12: Who built the first vacuum tube in 1838?
A) Heinrich Geissler
B) Wilhelm Roentgen
C) Johann Hittorf
D) William Crookes
ANS: A
Rationale: Heinrich Geissler built the first vacuum tube in 1838 .
Question 13: Who observed in 1870 that discharges emitted from the negative electrode of a vacuum
tube traveled in straight lines?
A) Heinrich Geissler
B) Wilhelm Roentgen
C) Johann Hittorf
D) William Crookes
ANS: C
Rationale: Johann Hittorf observed in 1870 that discharges emitted from the negative electrode of a
vacuum tube traveled in straight lines .
Question 14: Who discovered in the late 1870s that cathode rays were streams of charged particles?
A) Heinrich Geissler
B) Wilhelm Roentgen
C) Johann Hittorf
D) William Crookes
ANS: D
Rationale: William Crookes discovered in the late 1870s that cathode rays were streams of charged
particles .
Question 15: Who introduced the paralleling technique in 1896?
A) C. Edmund Kells
B) Franklin W. McCormack
C) F. Gordon Fitzgerald
D) Howard Riley Raper
ANS: A
Rationale: C. Edmund Kells introduced the paralleling technique in 1896 .
