Chapter 01: Introduction to Radiography
Ehrlich: Patient Care in Radiography: With an Introduction to Medical Imaging, 9th Edition

MULTIPLE CHOICE

	1.	X-rays were discovered in 1895 by:
a.	Coolidge.	
b.	Crookes.	
c.	Roentgen.	
d.	Edison.	

ANS:	C	REF:	p. 2	OBJ:	1

	2.	Of the following types of electromagnetic energy, which has the shortest wavelength?
a.	Radio waves	
b.	X-rays	
c.	Visible light	
d.	Ultraviolet light	

ANS:	B	REF:	p. 7	OBJ:	7

	3.	Which of the following is NOT an accurate statement regarding the characteristics of x-rays?
a.	They can penetrate matter that is impenetrable to light.	
b.	They cause certain crystals to fluoresce.	
c.	They can be refracted by a lens.	
d.	They cannot be detected by the human senses.	

ANS:	C	REF:	pp. 7-8	OBJ:	8

	4.	An electron cloud surrounding a hot cathode is referred to as a(n):
a.	focusing cup.	
b.	ampere.	
c.	space charge.	
d.	filament.	

ANS:	C	REF:	p. 6	OBJ:	6

	5.	The purpose of rotating the x-ray tube target is to:
a.	create a space charge.	
b.	remove long-wavelength photons from the x-ray beam.	
c.	focus the electron stream on a small target area.	
d.	increase the heat capacity of the anode.	

ANS:	D	REF:	p. 9	OBJ:	6

	6.	An imaginary photon that is emitted from the center of the focal spot, perpendicular to the long axis of the x-ray tube, is called the:
a.	electron stream.	
b.	x-ray beam.	
c.	central ray.	
d.	radiation field.	

ANS:	C	REF:	p. 8	OBJ:	10

	7.	A device used to control the size of the radiation field is a:
a.	collimator.	
b.	detent.	
c.	tube housing.	
d.	filter.	

ANS:	A	REF:	p. 8	OBJ:	11

	8.	The function of an x-ray grid is to:
a.	decrease patient radiation dose.	
b.	increase radiographic resolution.	
c.	increase radiographic contrast by reducing scatter radiation fog.	
d.	increase radiographic density.	

ANS:	C	REF:	p. 14	OBJ:	11

	9.	The majority of radiography education programs today are based in:
a.	proprietary schools.	
b.	hospitals.	
c.	clinics.	
d.	colleges.	

ANS:	D	REF:	p. 4	OBJ:	3

	10.	The container for the vacuum of the x-ray tube is made of:
a.	glass.	
b.	aluminum.	
c.	tungsten.	
d.	carbon.	

ANS:	A	REF:	p. 5	OBJ:	4

	11.	X-rays are a type of:
a.	electricity.	
b.	microwave.	
c.	kinetic energy.	
d.	electromagnetic energy.	

ANS:	D	REF:	p. 6	OBJ:	7

	12.	The frequency of an electromagnetic sine wave is defined as:
a.	the distance from trough to crest.	
b.	the distance from one crest to the next.	
c.	the number of times per second that a crest passes a given point.	
d.	the velocity at which the wave travels through space.	

ANS:	C	REF:	p. 6	OBJ:	9

	13.	Which of the following formulas represents the relationship between the wavelength, frequency, and velocity of an electromagnetic wave?
a.	f = λ ´ v	
b.	V = λ ´ f	
c.	Λ = f ÷ v	
d.	f = λ ÷ v	

ANS:	B	REF:	p. 6	OBJ:	9

	14.	Which of the following substances is most readily penetrated by x-rays?
a.	Water	
b.	Air	
c.	Bone	
d.	Fat	

ANS:	B	REF:	p. 7	OBJ:	8

	15.	Grids or buckys are generally used for body parts that measure greater than:
a.	2 to 4 cm.	
b.	10 to 12 cm.	
c.	18 to 20 cm.	
d.	30 cm.	

ANS:	B	REF:	p. 15	OBJ:	11

	16.	The access point for the radiographer to determine the exposure factors and to initiate the exposure is called the:
a.	transformer.	
b.	image receptor unit.	
c.	control console.	
d.	stationary grid.	

ANS:	C	REF:	p. 16	OBJ:	11

	17.	An x-ray machine designed for direct viewing of the x-ray image is called a(n):
a.	image receptor.	
b.	transformer.	
c.	control console.	
d.	fluoroscope.	

ANS:	D	REF:	p. 17	OBJ:	11

	18.	A device located between the x-ray tube and the control panel that increases the voltage delivered from the power company is called a:
a.	collimator.	
b.	transformer.	
c.	control console.	
d.	fluoroscope.	

ANS:	B	REF:	p. 16	OBJ:	11

	19.	The anode or positive end of the x-ray tube is the end that contains the:
a.	target.	
b.	filament.	
c.	focusing cup.	
d.	space charge.	

ANS:	A	REF:	p. 6	OBJ:	5

	20.	The inventor of the fluoroscope, who also investigated hundreds of fluorescent materials, was:
a.	Coolidge.	
b.	Pupin.	
c.	Roentgen.	
d.	Edison.	

ANS:	D	REF:	p. 3	OBJ:	2

	21.	The inventor of the hot cathode x-ray tube, the prototype of the x-ray tubes of today, was:
a.	Coolidge.	
b.	Pupin.	
c.	Roentgen.	
d.	Edison.	

ANS:	A	REF:	p. 3	OBJ:	2