Which of the following statements regarding dual x ray absorptiometry is (are true)

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What part's of the body should be shielded from the useful beam whenever possible?
Which of the following a device used to ensure reproducible radiographs regardless of tissue density variations is the?
Which of the following is used in digital fluoroscopy replacing the image intensifier's television camera tube?

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Question	Answer
The image intensifier's input phosphor is generally composed of A) cesium iodide B) zinc cadminum sulfide C) gadolinium oxysulfide D) calcium tungstate	A
Which of the following formulas would the radiographer use to determine the total number of heat units produced with a given exposure using three phase, twelve pulse equipment?	A) mA x time x kVp B) mA x time x kVp x 3.0 C) mA x time x kVp x 1.35 D) mA x time x kVp x 1.41 D
Star and Wye configurations are related to A) autotransformers B) three phase transformers C) rectification systems D) automatic exposure controls	B
Which of the following terms describes the amount of electric charge flowing per second? A) voltage B) current C) resistance D) capacitance	B
During a fluoroscopic examination, the milliamperage is A) less than 5 B) 10 to 20 C) 50 to 75 D) 100 to 500	A
The total brightness gain of an image intensifier is a result of 1. flux gain 2. minification gain 3. focusing gain A) 1 only B) 2 only C) 1 and 2 only D) 1 and 3 only	C
How many half-value layers will it take to reduce an x-ray beam whose intensity is 78R/min to an intensity of 10R/min?	3
When the radiographer selects kilovoltage on the control panel, which device is adjusted? A) step-up transformer B) autotransformer C) filament circuit D) rectifier circuit	B) autotransformer
Which of the following devices is used to control voltage by varying resistance? A) autotransformer B) high-voltage transformer C) rheostat D) fuse	C) rheostat
Which of the following occurs during bremsstrahlung radiation production?	an electron approaching a positive nuclear charge changes direction and looses energy
The photoelectric process is an interaction between an x-ray photon and A) an inner-shell electron B) an outer-shell electron C) a nucleus D) another photon	A) an inner-shell electron
Congruence of the x-ray beam with the light field is tested using A) a pinhole camera B) a star pattern C) radiopaque objects D) a slit camera	C) radiopaque objects
In fluoroscopy, the automatic brightness control adjusts the A) kVp and mA B) backup timer C) mA and time D) kVp and time	D) kVp and mA
A mobile C-arm can provide 1. fluoroscopic images 2. dynamic images 3. static images A) 1 only B) 1 and 2 only C) 2 and 3 only Feedback: s11 D) 1, 2 and 3	D
Which of the following pathologic conditions will probably require a decrease in exposure factors? A) Osteomylelitis B) Osteoporosis C) Osteosclerosis D) Osteochondritis	Osteoporosis
Protective devices such as lead aprons function to protect the user from1. remnant radiation2. primary beam3. scattered radiation A) 2 only B) 3 only C) 1 and 2 only D) 1, 2 and 3	B
Why are a single intensifying screen and single-emulsion film used for select radiographic examinations? A) decrease patient dose Feedback: s203 B) achieve longer scale of contrast C) better recorded detail D) decreased fiscal expenses	C) better recorded detail
Film base is currently made of which of the following materials? A) cellulose nitrate A) cellulose acetate C) polyester D) glass	C) polyester
A lateral radiograph of the cervical spine was made at 40"SID using 100 mA and 0.1 s exposure. If it is desired to increase the distance to 72", what should be the new mA, all other factors remaining the same, to obtain a like density image?	A) 100mA B) 200mA C) 300mA D) 400mA C
Which of the following projections of the abdomen may be used to demonstrate air or fluid levels? 1. Dorsal decubitus 2 Lateral decubitus 3. AP Trendelenburg A) 1 only B) 1 and 2 only C) 1 and 3 only D) 1, 2 and 3	B
Which of the following positions will demonstrate the right axillary ribs? 1. RAO 2. LAO 3. RPO A) 1 only B) 1 and 2 only C) 2 and 3 only D) 1, 2 and 3	C
All of the following bones are associated with condyles except the A) femur B) tibia C) fibula D) mandible	C
The lamina is represented by what part of the "scotty dog" seen in a correctly positioned oblique lumbar spine?	Body
During chest radiography, the act of inspriration: 1. elevates the diaphragm 2. raises the ribs 3. depresses the abdominal viscera A) 1 only B) 1 and 2 only C) 2 and 3 only D) 1, 2 and 3	C
Which of the following projections will best demonstrate the tarsal navicular free of superimposition? A) AP oblique, medial rotation B) AP oblique, lateral rotation C) mediolateral D) lateral weight-bearing	A
In the lateral projection of the ankle, the 1. foot is dorsiflexed 2. talar domes are superimposed 3. Distal fibula is visualized in posterior tibia A) 1 only B) 2 only C) 1 and 3 only D) 1, 2 and 3	D
Which of the following may be used to evaluate the glenohumeral joint space? 1. scapular Y projection 2. inferosuperior axial 3. grashey A) 1 only B) 1 and 2 only C) 2 and 3 only D) 1, 2 and 3	C
Types of moving grid mechanisms include 1. oscillating 2. reciprocating 3. synchronous A) 1 only B) 1 and 2 only C) 1 and 3 only D) 2 and 3 only	B
Which of the following is most likely to produce a radiograph with a long scale of contrast? A) increased photon energy B) increased screen speed C) increased mAs D) increased SID	A
When green-sensitive rare earth screens are properly matched with the correct film, what type of safelight should be used in the darkroom? A) Wratten 6B B) GBX or GS1 C) Amber D) none	B
In order to be suitable for use in intensifying screens, a phosphor should have which of the following characteristics?1. high conversion efficiency 2. high x-ray absorption 3. high atomic number A) 1 only B) 3 only C) 1 and 2 only D) 1, 2 a	D
Exposure factors of 90 kVp and 4 mAs are used for a particular nongrid exposure. What should be the new mAs if an 8:1 grid is added? A) 8 mAs B) 12 mAs C) 16 mAs D) 20 mAs	C
Which of the following groups of exposure factors will produce the greatest radiographic density? A) 100 mA, 0.03 s B) 200 mA, 0.10 s C) 400 mA, 0.03 s D) 600 mA, 0.03 s	B
Radiographic contrast is a result of 1. differential tissue absorption 2. emulsion characteristics 3. proper regulation of mAs A) 1 only B) 1 and 2 only C) 1 and 3 only D) 1, 2 and 3	B
With all other factors constant, as a digital image matrix size increases, 1. pixel size decreases 2. resolution increases 3. pixel size increases A) 1 only B) 2 only C) 1 and 2 only D) 2 and 3 only	C
Which of the following personnel monitoring devices used in diagnostic radiography is considered to be the most sensitive and accurate? A) TLD B) film badge C) OSL D) pocket dosimeter	C
To within what percentage of the SID must the collimator light and actual irradiated area be accurate? A) 2 percent B) 5 percent C) 10 percent D) 15 percent	A
What is the effect on relative biologic effectiveness (RBE) as LET increases? A) As LET increases, RBE increases B) As LET increases, RBE decreases C) As LET increases, RBE stabilizes D) LET has no effect on RBE	A
Methods of reducing radiation exposure to patients and / or personnel include 1. beam restriction 2. shielding 3. high-kV, low mAs factors A) 1 only B) 1 and 2 only C) 2 and 3 only D) 1, 2 and 3	D
What is the term used to describe x-ray photon interaction with matter and the transference of part of the photon's energy to matter? A) absorption B) scattering C) attenuation D) divergence	B
What is the intensity of scattered radiation perpendicular to and 1 meter from the patient compared to the useful beam at the patient's surface? A) 0.01 percent B) 0.1 percent C) 1.0 percent D) 10 percent	B
n the production of characteristic radiation the incident electron A) electrons drop to inner shells releasing energy B) ejects an outer-shell electron C) is deflected, with resulting energy loss D) is deflected with resulting energy increase	A
The stomach of an hypersthenic patient is most likely to be located A) high, transverse and lateral B) low, transverse and lateral C) high, vertical and toward midline D) low, vertical and toward midline	A
Shoulder arthrography may be performed to demonstrate a 1. torn synovial capsule 2. Baker's cyst 3. torn rotator cuff A) 1 and 2 only B) 1 and 3 only C) 2 and 3 only D) 1, 2 and 3	B
T-tube cholangiography is performed A) preoperatively B) during surgery C) postoperatively D) with a Chiba needle	C
Which of the following procedures will best demonstrate the cephalic, basilic and subclavian vessels? A) aortofemoral arteriogram B) upper limb arteriogram C) lower limb venogram D) upper limb venogram	D
In which type of fracture are the splintered ends of bone forced through the skin? A) closed B) compound C) compression D) depressed	B
Conditions contributing to poor radiographic film archival quality include 1. fixer retension 2. insufficient developer replenisher 3. poor storage conditions A) 1 only B) 3 only C) 2 and 3 only D) 1, 2 and 3	D
When a patient with an arm injury needs help in undressing, the radiographer should A) Remove clothing from the injured arm first B) Remove clothing from the uninjured arm first C) Always remove clothing from the left arm first D) Always cut clothin	B
Which of the following may be used to effectively reduce the viscosity of contrast media? A) Warming B) Refrigeration C) Storage at normal room temperature D) Storage in a cool, dry place	A
Which of the following legal phrases defines a circumstance in which both the health-care provider's and patient's actions contributed to an injurious outcome? A) Intentional misconduct B) Contributory negligence C) Gross negligence D) None of the a	B
Ingestion of a gas producing powder or crystals is usually preliminary to which of the following examinations? 1. Oral cholecystogram 2. Double contrast GI 3. Double contrast BE A) 1 only B) 2 only C) 2 and 3 only D) 1 and 3 only	B
In reviewing a patient's blood chemistry which of the following creatinine ranges is considered normal? A) 0.6 to 1.5 mg/100ml B) 4.5 to 6 mg/100ml C) 8 to 25 mg/100ml D) up to 50 mg/100ml	A
An inanimate object that has been in contact with an infectious microogranism is termed a A) vector B) fomite C) host D) reservoir	B
While performing mobile radiography on a patient, you note that the requisition is for a chest film to check placement of a Swan-Ganz catheter. A Swan-Ganz catheter is a(n) A) pacemaker B) chest tube C) intravenous catheter D)intra-arterial cathete	C
The condition that allows blood to shunt between the pulmonary artery and aorta is called A) patent ductus arteriosus B) coarctation of the aorta C) atrial septal defect D) ventricular septal defect	A
Examples of synovial pivot articulations include the 1. atlantoaxial joint 2. radioulnar joint 3. temporomandibular joint A) 1 only B) 1 and 2 only C) 2 and 3 only D) 1, 2 and 3	B
Which of the following criteria is (are) required for visualization of the greater tubercle in profile? 1. epicondyles perpendicular to the IR 2. arm in external rotation 3. humerus in AP position	2 and 3 only
Which of the following criteria are used to evaluate a PA projection of the chest? 1. ten posterior ribs should be visualized above diaphragm 2. sternoclavicular joints should be symmetrical 3.scapulae should be lateral to the lung fields	1, 2 and 3
In which projection of the foot are the talar domes best demonstrated? A) lateral oblique foot B) medial oblique foot C) lateral foot D)weight bearing foot	C
Which of the following statements is (are) correct regarding the PA Axial (Caldwell) skull 1. head is rested on forehead 2. OML is perpendicular to film 3. Petrosa are located in upper 1/3 of orbit	1 and 2 only
A lateral projection of the hand in extension is often recommended to evaluate 1. fracture 2. foreign body 3. soft tissue	2 and 3 only extension with fracture could displace bony fragments and cause additional pain
Which of the following is (are) best demonstrated in an oblique cervical spine image? 1. intervertebral foramina 2. pedicles 3. apophyseal joints	1 and 2 only
Which of the following positions is required in order to demonstrate blood in the pleural cavity? A) lateral decubitus, affected side up B) lateral decubitus, affected side down C) AP Trendelenburg D) AP supine	B
Which of the following is a radiologic procedure that functions to dilate a stenotic vessel? A) percutaneous nephrolithotomy B) percutaneous angioplasty C) renal arteriography D) surgical nephrostomy	B
The input phosphor of the image intensifier tube functions to convert A) kinetic energy to light B) x-rays to light C) electrons to light D) fluorescent light to electrons	B
Which of the following positions is most likely to offer the best visualization of the pulmonary apices? A) lateral decubitus B) dorsal decubitus C) erect PA D) AP axial lordotic	D
A radiographer who discloses confidential information to unauthorized individuals may be found guilty of A) invasion of privacy B) slander C) libel D) defamation	A
The biggest advantage of coupling the image intensifier to the TV camera or CCD via a lens coupling device is its A) compact size B) durability C) ability to accommodate cine and /or spot films D) ease of maneuverability	C
Which type of error results in grid cutoff at the periphery of the radiographic image? A) Off focus B) Off level C)Off angle	A
The annual dose limit for medical imaging personnel includes radiation from 1. medical x-rays 2. occupational exposure 3. background radiation	2 only
According to National Council on Radiation Protection and Measurements (NCRP) regulations, leakage radiation from the x-ray tube must not exceed A) 10mR/h B) 100mR/h C) 10mR/min D) 100mR/min	B
The amount of time that x-rays are being produced and directed toward a particular wall is referred to as the A) workload B) use factor C) occupancy factor D) controlling factor	B
Which of the following are demonstrated in the lateral projectionof the thoracic spine? 1. intervertebral disk spaces 2. apophyseal joints (zygophyseal) 3. intervetebral foramina	1 and 3 only
In the AP axial projection (Towne) of the skull, with the central ray directed 30 degrees caudad to the orbitomeatal line and passing midway between the external auditory meatus, which of the following is best demonstrated?	Occipital Bone
Sterile technique is required when contrast agents are adminitered A) rectally B) orally C) intrathecally D) through a nasogastric tube	C
Abnormal accumulation of blood between the visceral and parietal pleura in the thorax is called A) emphysema B) empyema C) pneumothorax D) hemothorax	D
Instruments required to assess vital signs include 1. sphygmomanometer 2. watch with a second hand 3. tongue blade	1 and 2 only
The type of shock associated with infection is classified as A) neurogenic B) cardiogenic C) hypovolemic D) septic	D
If extravasation occurs during an intravenous injection of contrast media, correct treatment includes which of the following? 1. remove needle and immediately seek another vein 2.apply pressure to the vein until bleeding stops 3. apply warm, moist he	2 and 3 only
When disposing of a contaminated needle, it is placed in a special container following what procedure?	do not recap needle and dispose of the entire syringe
That plane that passes vertically through the body dividing it into equal right and left portions is called: A) coronal plane B) sagittal plane C) transverse plane D) midsagittal plane	D
With the patient recumbent and head positioned at a higher level than the feet, the patient is said to be in the : A) Trendelenburg position B) Fowler's position C) decubitus position D) Sims' position	B
The relationship between the midsagittal and midcoronal planes is: A) perpendicular B) parallel C) 45 degrees D) 70 degrees	A
Identify that topographic anatomy which most closely corresponds with T10 A) costal margin B) inferior angle of scapula C) xiphoid tip D) umbilicus	C
Which of the following should not be performed until a transverse fracture of the patella has been ruled out? 1. AP knee 2. lateral knee 3. axial/tangential patella	2 and 3 only
The proximal tibiofibular articulation is best demonstrated in which of the following positions? A) medial oblique 45 degrees B) lateral oblique C) medial oblique mortise D) lateral	A
The quality factor for x-rays is: A) 1 B) 5 C) 10 D) 100	A
One hundred ergs of energy deposited per gram of tissue defines the: A) becquerel B) gray C) rad D) quality factor	C
Rem multiplied by a quality factor equals A) Rad B) Roentgen C) Gray D) No such equation is used	D
Radiation protection is based on which dose response relationship? A) linear threshold B) linear nonthreshold C) nonlinear nonthreshold D) nonlinear threshold	B
Which of the following causes about 95% of the cellular response to radiation? A) direct effect B) indirect effect C) target theory D) Law of Bergonie and Tribondeau	B
The absorbed dose equivalent limit for the embryo/fetus is: A) 500 mrem per year B) 5 rem per year C) 0.5 rem per month D) 500 mrem during gestation	D
The SI unit of dose equivalency is the: A) Rem B) Sievert C) Gray D) Quality factor	B
XRays travel as bundles of energy called: A) particles B) protons C) Quanta D) Quarks	C
The filament circuit uses what type of transformer? A) Step-down B) Autotransformer C) Falling load D) Step-up	A
Where is the rectifier located in the x-ray circuit?	Between the step-up transformer and the x-ray tube
When a quality control test for accuracy of kVp is performed, the result must be within this amount of the control panel setting.... A) 2% of SID B) 4 keV C) 4% of kVp D) 10% of SID	B
Distance and density are governed by what law or rule? A) Reciprocity law B) 15% law C) Density maintenance rule D) Inverse square law	D
The speed step on a characteristic curve of a particular film is identified as: A) 0.25 B) 0.5 C) 1.0 D) 2.0	C
The speed step used during sensitometric testing is the step closest to: A) 0.25 +B+F B) 0.5 C) 1.0+B+F D) 2.0	C
The wash tank of an automatic processor should be drained every: A) day B) week C) month D) year	A
Poor developer replenishment will cause A) light films B) dark films C) milky films D) greasy films	A
Contamination of the fixer by overflow of developer will: A) result in light films B) will result in dark films C) Will not change the density of the film D) cause tacky films	C
The proper SID at which a grid may be used is called: A) grid radius B) grid ratio C) grid retention D) grid rodeo	A
A backup timer for the automatic exposure control serves to: 1. protect the patient form overexposure 2. protect the x-ray tube from excessive heat 3. eventually increase inherent filtration	1 and 2 only
Patient dose can be decreased by using: 1. high speed film and screen combination 2. high ratio grids 3. air gap technique A) 1 only B) 1 and 2 only C) 1 and 3 only D) 1, 2 and 3	A
The quality assurance term used to describe consistency in exposure with adjacent mA stations and exposure times adjusted to produce the same mAs is: A) automatic exposure control B) positive beam limitation C) linearity D) reproducibility	C
The effects of radiation to biologic material are dependent on several factors. If a quantity of radiation is delivered to a body over a long period of time, the effect:	A) will be greater than if it were delivered all at one time B) will be less than if it were delivered all at one time C) has no relation to how it is delivered in time D) is solely dependent on the radiation quality B
Those radiation effects, demonstrated on a dose response curve as being threshold and linear, represent a group of effects called: A) deterministic B) stochastic C) severe D) fatal	A
Which of the following accounts for x-ray beam heterogeneity? 1. incident electrons interacting with several layers of tungsten target atoms 2. electrons moving to fill different shell vacancies 3. its nuclear origin	1 and 2 only
How are wavelength and energy related? A) directly B) inversely C) chemically D) empirically	B
How much protection is provided from a 75 kVp x-ray beam when using a 0.50mm lead equivalent apron? A) 65% B) 75% C) 88% D) 99%	C 0.5mm equivalent apron will attenuate about 99% of scatter at 50kVp 88% at 75 kVp 75% at 100 kVp
Primary radiation barriers must be at least how high? A) 5 feet B) 6 feet C) 7 feet D) 8 feet	C
During routine intravenous urography, the oblique position demonstrates the: A) kidney of side up parallel to the IR B) kidney of the side up perpendicular to the IR C) urinary bladder parallel to the IR D) urinary bladder perpendicular to the IR	A
Which of the following gauge needles has the largest bore? A) 12 B) 18 C) 20 D) 23	A
If a student radiographer who is younger than 18 years begins clinical assignments, what is his or her annual dose limit? A) 0.1 rem (1mSv) B) 0.5 (5mSv) C) 5 rem (50 mSv) D) 10 rem (100mSv)	NCRP Report No.105 and Code of Federal Regulations (10 CFR 20) under 18 and in profession = 0.1rem 18 yrs and over = 5 rem general population = 1/10 of ours 0.5 rem
An optically luminescent dosimetry system uses which of the following crystals? A) silver bromide B) aluminum oxide C) lithium floride D) ferrous sulfate	B
The purpose of filters in a film badge is: A) eliminate harmful rays B) measure radiation quality C) prevent exposure from alpha particles D) as support for film contained within	B
Which of the following is a measure of dose to biologic tissue? A) roentgen (C/kg) B) rad (Gy) C) rem (Sv) D) REB (relative biological effectiveness)	C
Recognizing that a vasodilator would most likely be used for angina, identify the vasodilator from the choices below A) atropine B) epinephrine C) diphenhydromine D) nitroglycerin	D
Identify from the choices below - that condition which would not benefit from an esophogram. A) dysphagia B) achalasia C) varices D) dysphasia	D
In which projection of the foot are the tarsal joint spaces and the heads of the metatarsals best demonstrated? A) medial oblique foot B) lateral oblique foot C) AP foot D) lateral foot	C
During intravenous (IV) urography, the upright post void position is generally recommended to demonstrate 1. filling of ureters 2. renal pelvis 3. superior calyces	1 only
Which of the following would be the best choice for a right shoulder exam to rule out fracture? A) internal and external rotation B) AP and tangential C) AP and AP axial D) AP and scapular Y	D
Which of the following is a functional study of the urinary tract? A) Retrograde pyelogram B) Cystogram C) Voiding cystourethrogram D) Percutaneous nephrostomy	C
The AP projection of the sacrum requires that the central ray be directed 1. 15 degrees cephalad 2. midway between ASIS and the pubic symphysis 3. midline at the level of the greater trochanter	1 and 2 only
Which of the following radiographic procedures requires contrast be injected into the renal pelvis via catheter placement within the ureter? A) nephrotomography B) retrograde urography C) cystourethrography D) IVU	B
Which of the following are characteristic of the hypersthenic body type? 1. short, wide, transverse heart 2. high and peripheral large bowel 3. diaphragm positioned low	1 and 2 only
Which of the following conditions is often the result of ureteral obstruction or stricture? A)pyelonephrosis B) nephrotosis C) hydronephrosis D) cystourethritis	C
The major arteries supplying the brain include the 1. brachiocephalic artery 2. common carotid arteries 3. vertebral arteries	C
The dose of radiation that will cause a noticeable skin reaction is referred to as the A) linear energy transfer (LET) B) source to skin distance (SSD) C) skin erythema dose (SED) D) source-image distance (SID)	C
Radiographers use monitoring devices to record their monthly exposure to radiation. The types best suited for this purpose include the 1. pocket dosimeter 2. thermoluminescent dosimeter 3. optically stimulated luminescence dosimet	2 and 3 only
If the exposure rate to an individual standing 2 m from a source of radiation is 15R/min, what will be the dose received after 2 min at a distance of 5m from the source? A) 1.2R B) 2.4R C) 4.8R D) 9.6R	C
Late or long-term effects of radiation exposure are generally represented by which of the following dose-response curves? A)linear threshold B) linear nonthreshold C) nonlinear threshold D) nonlinear nonthreshold	B
The recommendation of "elective booking" states that elective abdominal radiographic examinations on wome of reproductive age should be limited to the	10 days following the onset of menses
What is the established fetal dose limit guideline for pregnant radiographers during the entire gestation period? A) 100mrem B) 250mrem C) 500mrem D) 1000mrem	C
Irradiation of water molecules within the body, and their resulting breakdown, is termed A) epilation B) proliferation C) radiolysis D) repopulation	C
The x-ray interaction with matter that is responsible for the majority of scatter radiation reaching the film is A) photoelectric effect B) Compton scatter C) classical scatter D) Thompson scatter	B
A thermoluminescent dosimetry system would use which of the following crystals? A) silver bromide B) sodium sulfite C) lithium fluoride D) aluminum oxide	C
The photoelectric effect is an interaction between an x-ray photon and A) an inner-shell electron B) an outer-shell electron C) a nucleus D) another photon	A
In radiation protection, the product of absorbed dose and the correct modifying factor (rad X QF) is used to determine A) roetgen (C/kg) B) rem (SV) C) rad (Gy) D) radiation quality	B
How does filtration affect the primary beam? A) it increases the average energy of the primary beam B) it decreases the average energy of the primary beam C) it makes the primary beam more penetrating D) it increases the intensity of the primary bea	A
Immature cells are referred to as 1. undifferentiated cells 2. stem cells 3. genetic cells	1 and 2 only
To be in compliance with radiation safety standards, the fluoroscopy exposure switch must A) sound during fluoro-on time B) be on a 6 ft long cord C) terminate fluoro after 5 min D) be the dead-man type	D
Which of the following types of gonadal shielding would be best suited for fluoroscopic examinations? 1. flat contact 2. shaped contact 3. shadow	1 and 2 only
The law of Bergonie and Tribondeau states that cells are more radiosensitive if they are 1. highly mitotic 2. undifferentiated 3. mature cells	1 and 2 only
The reduction in the intensity of an x-ray beam as it passes through material is termed? A) absorption B) scattering C) attenuation D) divergence	C
What unit of measure expresses the amount of energy deposited in tissue? A) Roentgen (C/kg) B) Rad (Gy) C) Rem (Sv) D) Realitive biological exposure (RBE)	B
Which of the following accounts for the x-ray beam's heterogeneity? 1. incident electrons interacting with several layers of tungsten target atoms 2. energy differences among incident electrons 3. electrons moving to fill different shell vacanc	1, 2 and 3
Which of the following contributes most to occupational exposure? A) photoelectric effect B) Compton scatter C) Classical scatter D) Thompson scatter	B
The focal spot to table distance in mobile fluoroscopy, must be A) a minimum of 15 in B) a maximum of 15 in C) a minimum of 12 in D) a maximum of 12 in	C
LET is best defined as 1. a method of expressing radiation quality 2. a measure of the rate at which radiation energy is transferred to soft tissue 3. absorption of polyenergetic radiation	1 and 2 only
Stochastic effects of radiation are those that 1. have a threshold 2. may be described as "all of nothing" effect 3. are late effects A) 1 only B) 1 and 2 only C) 2 and 3 only D) 1, 2 and 3	C
When a slow screen/film system is used with a fast screen/film automatic exposure control system the resulting images A) are too light B) are too dark C) have improved detail D) have poor detail	A
With all other factors constant, as a digital image matrix size increases, 1. pixel size decreases 2. resolution increases 3. pixel size increases	1 and 2 only
Of the following groups of exposure factors which will produce the greatest radiographic density? A) 200 mA, 0.03 s, 72 in SID B) 100 mA, 0.03 s, 36 in SID C) 100mA, 0.06 s, 36 in SID D) 200 mA, 0.06 s, 72 in SID	C
Decreasing field size from 14 X 17 to 8 X 10 will	decrease radiographic density and decrease the amount of scatter radiation generated within the part
Exposure factors of 90 kVp and 4 mAs are used for a particular nongrid exposure. What should be the new mAs if an 8:1 grid is added? A) 8 mAs B) 12 mAs C) 16 mAs D) 20 mAs	C
In a PA projection of the chest being used for cardiac evaluation, the heart measures 15.2cm between its widest points. If the magnification factor is known to be 1.3, what is the actual diameter of the heart? A) 9.7 cm B) 11.7 cm C) 19.7 cm D) 20.	B
Quantum mottle is most obvious when using A) slow-speed screens B) rare-earth screens C) fine-grain film D) minimal filtration	B
When green-sensitive rare earth screens are properly matched with the correct film, what type of safelight should be used in the darkroom? A) Wratten 6B B) GBX or GS1 C) Amber D) none	B
The relationship between the intensity of light striking a film and the intensity of light transmitted through the film is an expression of which of the following?	A) radiographic contrast B) radiographic density C) recorded detail D) radiographic filtration B
Exposed silver halide crystals are changed to black metallic silver by the A) preservative B) reducers C) activators D) hardener	B
Types of moving grid mechanisms include 1. oscillating 2. reciprocating 3. synchronous	1 and 2 only
Structures forming the brain stem include:1. pons2. medula oblongata3. midbrain	1, 2 and 3
Which of the following statements regarding the Norgaard method, "Ball-Catcher's position" is (are) correct?1. Bilateral AP oblique hands are obtained2. It is used for early detection of rheumatoid arthritis3. The hands are lateral with spread fingers	1 and 2 only
Which of the following units is(are) used to express resolution?1. line-spread function2. line pairs per millimeter3. line focus principle	1 and 2 only
In electronic imaging, as digital image matrix size decreases,1. pixel sized decreases2. resolution decreases3. pixel depth decreases	2 only
) 2 only	A
Voltage ripple associated with a three phase, six-pulse rectified generator is about: A) 100% B) 32% C) 13% D) 3%	C
The functions of a picture archiving and communication system (PACS) include1. storage of analog images2. acquisition of digital images3. storage of digital images A) 1 only B) 1 and 2 only C) 2 and 3 only D) 1, 2 and 3	C
Which of the following statements regarding dual x-ray absorptiometry is (are) true?1. it is a low-dose procedure2. two x-ray photon energies are used3. photon attenuation by bone is calculated A) 1 only B) 1 and 2 only C) 1 and 3 only D) 1, 2 and 3	D
Ther term "parenteral" refers to the following medication routes?1. subcutaneous2. intramuscular3. oral A) 1 only B) 1 and 2 only C) 2 and 3 only D) 1, 2 and 3	B
What percentage of x-ray attenuation does a 0.5mm lead equivalent apron at 75 kVp provide? A) 51% B) 66% C) 75% D) 88%	D
A radiograph exposed using a 12:1 ratio grid may exhibit a loss of density at its lateral edges because the A) SID was too great B) grid failed to move during the exposure C) x-ray tube was angled in the direction of the lead strips D) CR was off cent	A
In amorphous selenium flat-panel detectors, the term "amorphous" refers to a	A) crystalline material having typical crystalline structure B) crystalline material lacking typical crystalline structure C) toxic crystalline material D) homogeneous crystalline material B
A satisfactory radiograph was made without a grid using a 72" SID and 8 mAs. If the distance is changed to 40" and an 12:1 ratio grid is added, what should be the new mAs? A) 9.5 mAs B) 12 mAs C) 21 mAs D) 26 mAs	B
The most frequent site of nosocomial infection is the: A) urinary tract B) blood C) respiratory tract D) digestive tract	A
The device that is used for direct measurement of optical density is the A) sensitometer B) densitometer C) penetrometer D) Hurter and Driffield curve	B
The infection streptococcal pharyngitis ("strep throat") is caused by a A) virus B) fungus C) protozoon D) bacterium	D
Which of the following is a fast-acting vasodilator used to lower blood pressure and relieve the pain of angina pectoris? A) Digitalis B) Dilantin C) Cimetidine D) Nitroglycerin	D
What should be done to correct for magnification when using air-gap technique? A) Decrease OID B) Increase OID C) Decrease SID D) Increase SID	D
Which of the following groups of exposure factors would be most effective is eliminating prominent pulmonary vascular markings in an RAO positionof the sternum?	A) 500 mA, 1/30 s, 70 kVp B) 200 mA, 0.04 s, 80 kVp C) 300 mA, 1/10 s, 80 kVp D) 25 mA, 7/10 s, 70kVp D
Which of the following groups of technical factors will produce the greatest density? A) 400 mA, 0.01 s, 94 kVp, 100 speed screens B) 500 mA, 0.008 s, 94 kVp, 200 SS C) 200 mA, 0.04 s, 94 kVp, 50 SS D)100 mA, 0.02 s, 80 kVp, 200 SS	B -
If an individual receives 50mR while standing 4 ft from a source of radiation for 2 min, which of the options listed below will most effectively reduce his or her radiation exposure to that source?	A) standing 3 ft from source for 2 min B) standing 8 ft from source for 2 min C) standing 5 ft from source for 1 min D) standing 6 ft from source for 2 min B
In the AP axial projection (Towne) of the skull, with the central ray directed 30 degrees caudad to the orbitomeatal line and passing midway between the external auditory meatus, which of the following is best demonstrated?	A) occipital bone B) frontal bone C) facial bones D) basal foramina A

When an x

When x-rays exit the patient they reach the scintillator layer converting the energy carried by the x-rays into visible light. Energy from the visible light is transformed into electrical charges in the 2nd layer, these charges are then read out by the TFT array as in the direct conversion system.

What part's of the body should be shielded from the useful beam whenever possible?

Shielding, wherever possible is effective for protection of the patient's radio-sensitive organs, such as the breast, gonads, eyes and thyroid.

Which of the following a device used to ensure reproducible radiographs regardless of tissue density variations is the?

ARRT registry review covering Unit 2: Equipment Operation and Quality Control.

Which of the following is used in digital fluoroscopy replacing the image intensifier's television camera tube?

Equipment Operation and Quality Control.

When an x

Which of the following statements regarding dual x ray absorptiometry is (are true)

When an x

What part's of the body should be shielded from the useful beam whenever possible?

Which of the following a device used to ensure reproducible radiographs regardless of tissue density variations is the?

Which of the following is used in digital fluoroscopy replacing the image intensifier's television camera tube?

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