MIDTERM Qs {THE CRUCIAL QUARTER}

Question 1

1. An isotope of boron has 5 protons and 6 neutrons. The atomic number of boron is

a. 11
b. 10
c. 6
d. 5

Answer 1

d. 5

Question 2

2. If an electron is gained or lost from an atom, that atom becomes

a. an ion
b. a new element
c. an isotope
d. unstable

Answer 2

a. an ion

Question 3

3. 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

Answer 3

c. inhibit movement of electrical charge

Question 4

4. The electrons in an electrical current

a. all have the same velocity
b. flow from one end of the circuit to another
c. have a net motion in the direction opposite to the conventional current flow
d. none of the above

Answer 4

c. have a net motion in the direction opposite to the conventional current flow

Question 5

5. An induced current in a wire loop

a. results from a constant magnetic flux
b. can result only from an alternatively 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

Answer 5

b. can result only from an alternatively expanding and contracting magnetic field

Question 6

6. American generators operate at

a. 220 V
b. 120 AC
c. 60 Hz
d. 30 A

Answer 6

c. 60 Hz

Question 7

7. Backup time

a. cannot exceed the tube limit
b. is not needed for three-phase generators
c. should be set at 150 percent of expected manual mAs
d. both a and c

Answer 7

d. both a and c

Question 8

8. The incoming line current in modern high capacity x-ray units is supplied

a. in the form of a three-phase power cycle
b. in the form of a single-phase power cycle
c. as a direct current
d. at approximately 60 volts

Answer 8

a. in the form of a three-phase power cycle

Question 9

9. Driving the thermionic cloud from the cathode to the anode requires

a. a large potential difference
b. a small voltage
c. a large amperage
d. a small amperage

Answer 9

a. a large potential difference

Question 10

10. The focusing cup has a/an ___ charge.

a. neutral
b. atomic
c. positive
d. negative

Answer 10

d. negative

Question 11

11. The only portion of the anode assembly placed outside the vacuum of the envelope is the

a. stator
b. rotor
c. rotating disc
d. molybdenum neck

Answer 11

a. stator

Question 12

12. The types of target interaction that occur in the production of diagnostic-range x-ray photons are dependent upon

a. electron kinetic energy
b. nuclear binding energy
c. electron potential energy
d. both a and b

Answer 12

d. both a and b

Question 13

13. The quantity of x-rays or gamma rays required to produce a given amount of ionization in a unit mass of air defines the

a. kerma
b. gray
c. roentgen
d. curie

Answer 13

c. roentgen

Question 14

14. The annual effective dose limit for an occupational exposure to ionizing radiation is ___ rem.

a. 1
b. 0.1
c. 5
d. 0.5

Answer 14

c. 5

Question 15

15. Which atomic shell possesses the highest binding energy?

a. K
b. L
c. M
d. all atomic shells possess the same binding energy

Answer 15

a. K

Question 16

16. During the photoelectric interaction, as an electron transfers from an outer shell to a vacant inner shell, energy is released in the form of

a. a characteristic photon
b. a primary radiation
c. an incident electron
d. an incident photon

Answer 16

a. a characteristic photon

Question 17

17. The radiation intensity from a diagnostic x-ray unit will vary in a/an

a. direct relationship with mAs
b. direct relationship with the square of the kVp
c. inverse relationship with the square of the distance
d. all of the above

Answer 17

d. all of the above

Question 18

18. The speed of an imaging system depends on the

a. thickness of the phosphor or silver halide layer
b. crystal/phosphor size
c. efficiency of the crystal/phosphor
d. all of the above

Answer 18

d. all of the above

Question 19

19. The line focus principal allows for a large _______ for maximum heat load and a small ________ for increased detail in an image.

a. effective, actual
b. estimated, actual
c. actual, estimated
d. actual, effective

Answer 19

d. actual, effective

Question 20

20. Photoelectric interactions are __________ related to the Energy of the beam

a. inversely
b. directly
c. inversely cubed
d. directly cubed

Answer 20

c. inversely cubed