Exam 1

possesses a negative charge and minute mass (a. electron e. kinetic energy b. neutron f. atomic mass c. proton g. atomic number d. binding energy h. isotope)

A; electron

A transformer with more secondary windings than primary windings a. has a greater secondary voltage. b. is a step-down transformer. c. has a greater power output than input. d. has a higher power loss.

A; has a greater secondary voltage

If an electron is gained or lost from an atom, that atom becomes a. an ion. c. an isotope. b. a new element. d. unstable.

A; ionized

Electrical components possess a negative and a positive side. This polarity permits the application of a. resistance across the poles to inhibit electron flow. b. an electromotive force (emf) to enable current flow. c. a spark gap to check amperage. d. all of the above

B; an electromotive force (emf) to enable current flow.

An induced current in a wire loop a. results from a constant magnetic flux. b. can result only from an alternately expanding and contracting magnetic field. c. is in such a direction that its effects oppose the change producing the current. d. always decreases when the magnetic flux decreases.

B; can result only from an alternately expanding and contracting magnetic field.

Electric current is defined as a. time/charge. c. (charge)(time). b. charge/time. d. charge/time^2.

B; charge divided by time

Electrons move downward in a vertical wire. The direction of the associated magnetic field directly around the wire is a. clockwise. b. counterclockwise c. in the direction of the electron flow. d. opposite to the conventional current.

B; counterclockwise

A motor is a device that converts a. thermal energy into electrical energy. b. electrical energy into mechanical energy. c. electrical energy into electromagnetic energy. d. mechanical energy into electrical energy.

B; electrical energy into mechanical energy

When the atomic valence and conductance bands overlap, a. an insulator is created. b. electrical flow easily occurs. c. electrical flow is inhibited. d. Ohm's law no longer applies.

B; electrical flow easily occurs.

The unit of mass is the a. m/sec. c. mm. b. kg. d. cc.

B; kilogram

A gain or loss of this atomic particle creates an isotope. (a. electron e. kinetic energy b. neutron f. atomic mass c. proton g. atomic number d. binding energy h. isotope)

B; neutron

computer platforms used for medical patient care purposes

BMI

All of the following are true of electromagnetic energies EXCEPT: a. They are illustrated as sinusoidal waves. b. They possess both wave and particle characteristics. c. The relationship between frequency and wavelength is direct and proportional. d. They are arranged in an orderly spectrum according to frequency and wavelength.

C The relationship between frequency and wavelength is direct and proportional.

Photon wavelength is a. inversely proportional to photon velocity. b. directly proportional to photon frequency. c. inversely proportional to photon frequency. d. usually designated by the letter c.

C inversely proportional to photon frequency.

Isotopes have ____ mass numbers and ____ atomic numbers. a. the same; the same c. different; the same b. the same; different d. different; different

C; different mass numbers; same atomic numbers

Electric insulators a. convert electrical energy into heat. b. consist of materials like silicon. c. inhibit movement of electrical charge. d. permit movement of electrical charge.

C; inhibit movement of electrical charge

A generator is a device that converts a. electrical energy to thermal energy. b. thermal energy to electrical energy. c. mechanical energy to electrical energy. d. electrical energy to mechanical energy.

C; mechanical energy to electrical energy.

A change in the number of these changes the identity of the element. (a. electron e. kinetic energy b. neutron f. atomic mass c. proton g. atomic number d. binding energy h. isotope)

C; protons

The atomic number is the number of ____ contained in the nucleus. a. neutrons c. protons b. electrons d. positrons

C; protons

According to the "rule of octets" a. eight energy levels have electrons. b. eight protons occupy the outermost shell. c. the valence shell is chemically inert. d. both a and c

C; the valence shell is chemically inert. (stable)

Electric potential is measured in a. coulombs. c. volts. b. joules. d. ohms.

C; volts

The maximum number of electrons in a period with a principal quantum number of 4 is a. 6. c. 18. b. 8. d. 32.

D; 8

industry-standard language in medical imaging

DICOM

may have resolution as high as 3-5 megapixels

LCD

If the digital FOV is 1024 and the display matrix is 256, the pixel size would be a. 4. c. 768. b. 128. d. 262,144.

a. 4.

An eight-bit word is called a a. byte. c. bit. b. RAM. d. ROM.

a. byte.

Each pixel in a digital display matrix is located according to its a. electronic address. c. DICOM address. b. voxel position. d. FOV.

a. electronic address.

If the radiographer applied an ankle LUT to a chest radiograph data set, the image would demonstrate a. high contrast. c. very high resolution. b. low contrast. d. low resolution.

a. high contrast

The window level controls a. image density. c. speed. b. image contrast. d. brightness.

a. image density

A common feature between indirect and direct DR technology is a. thin film technology (TFT). c. cassettes. b. a scintillation layer. d. imaging plates (IP).

a. thin film technology (TFT)

The diagnostic x-ray range is approximately a. 10 to 1,200 mA. c. 25 to 150 kVp. b. 0.001 to 10 seconds. d. all of the above

all of the above

Match the following atomic structure characteristics with the correct statement or definition. 1. entirely concentrated in the nucleus (a. electron e. kinetic energy b. neutron f. atomic mass c. proton g. atomic number d. binding energy h. isotope)

atomic mass

All of the following are true of pixel pitch EXCEPT: a. It is defined as the distance between pixels. b. It is not related to spatial resolution. c. It is determined by the size of the DEL in DR systems. d. It is measured from the center-to-center of the pixels.

b. It is not related to spatial resolution.

An atom has an atomic number of 18 and a mass number of 38. Letting P = the number of protons and N = the number of neutrons, which of the following atoms is the isotope of this atom? a. P = 18, N = 20 c. P = 20, N = 18 b. P = 18, N = 21 d. none of the above

b. P = 18, N = 21

Medical images that are sent via teleradiology are sent over a a. HIS. c. LAN. b. WAN. d. DICOM.

b. WAN

Computers operate using a ____ language. a. monosyllabic source language c. logarithmic machine b. binary machine d. 26-letter symbolic

b. binary machine

Each binary number is called a a. pixel. c. byte. b. bit. d. voxel.

b. bit.

All of the following impact digital image spatial resolution EXCEPT a. pixel pitch. c. DEL dimension. b. bits/pixel. d. sampling frequency.

b. bits/pixel.

The window width controls a. image density. c. speed. b. image contrast. d. depth.

b. image contrast.

Noise on a digital image is the summation of inherent electron system noise and quantum mottle noise. Of these two, the radiographer can improve the noise on an image by a. decreasing the exposure intensity of the x-ray beam. b. increasing the exposure technique. c. turning off any electronic devices during exposures. d. all of the above

b. increasing the exposure technique.

Computerized digital images consist of a ________ of picture elements, each with a video display value or gray shade. a. row c. column b. matrix d. pixel

b. matrix

Resolution is controlled by ____ size. a. bit c. matrix b. pixel d. byte

b. pixel

In digital imaging, the limiting factor in spatial resolution is the a. pixel depth. c. bit depth. b. pixel size. d. pixel pitch.

b. pixel size.

Essential characteristics of a PACS include: 1. distribution and retrieval of digital images 2. creation of digital images 3. radiation dosage documentation 4. display of digital images 5. voice-activated dictation 6. digital image storage and long-term archival a. 1, 2, 4, and 5 only c. 1, 4, and 6 only b. 2, 3, 4, 5, and 6 only d. 1, 2, 3, 4, and 6 only

c. 1, 4, and 6 only ( 1. distribution and retrieval of digital images. 4. display of digital images 6. digital image storage and long-term archival)

American generators operate at a. 220 V. c. 60 Hz. b. 120 AC. d. 30 A.

c. 60 Hz

Any computer platform that is designed to deal with medical purposes such as medical care, medical information, and medical research and documentation would be classified as a/an a. HIS. c. BMI. b. ACR. d. BMR.

c. BMI.

A ____ connects all the computers in a system. a. WAN c. LAN b. DICOM d. CCD

c. LAN

All of the following are true of transformers EXCEPT: a. They have no moving parts. b. They work on the principle of mutual induction. c. They work most efficiently on pulsating DC. d. They are designed to regulate voltage.

c. They work most efficiently on pulsating DC

The purpose of a LUT is to a. determine the exposure index. b. create the histogram. c. apply a predetermined scale of contrast to the digital data set. d. perform geometric processing in order to reorient the image on display.

c. apply a predetermined scale of contrast to the digital data set.

In the technology of CR, the latent image is actually a. sensitivity specks in the barium fluorohalide. b. free electrons in the amorphous silicon. c. electron "holes" in Europium. d. the light from the phosphor following laser excitation of the reader assembly.

c. electron "holes" in Europium.

The orderly arrangement of elements in the periodic table is based upon a. atomic weights. c. neutron number. b. mass number. d. atomic number.

d. atomic number.

Soft copy display of images refers to a. unprocessed images b. pre-processed images c. images displayed on a lightbox d. images displayed via a video monitor

d. images displayed via a video monitor

The sum of protons and neutrons in a nucleus is called the a. electron number. c. quantum number. b. atomic weight. d. mass number.

d; mass number

Automatic exposure control (AEC) technology determines a. patient thickness. c. kVp. b. exposure time. d. mA.

exposure time.

a wide band gap

insulator

a device to control resistance

rheostat