Fall 24: Chapter 6 & 7 Quizzes

Question 1

A rheostat is located in which circuit?
A. Circuit Breaker
B. Secondary
C. Primary
D. Filament

Answer 1

D. Filament

Question 2

Which of the following accurately describes the solid-state rectifier?
A. A p-n crystal that only conducts electricity in 1 direction
B. 2 electrodes with electron traps
C. A device that insulates against electric shock
D. 2 semi-conducting crystals with free electrons

Answer 2

A. A p-n crystal that only conducts electricity in 1 direction

Question 3

Rectifier banks are located in where?
A. Primary side of the autotransformer
B. Secondary side of the filament transformer
C. Primary side of the high-tension transformer
D. Secondary side of the high tension-transformer

Answer 3

D. Secondary side of the high tension-transformer

Question 4

Why are rheostats necessary in the x-ray production process?
A. Control filament heating
B. Control anode temp
C. Adjust kV
D. Select focal spot

Answer 4

A. Control filament heating

Question 5

Which of the following best described the autotransformer?
A. 2 coils side by side
B. 2 coils wound together
C. 1 coil serving as both primary & secondary
D. An air gap between 2 electrodes

Answer 5

C. 1 coil serving as both primary & secondary

Question 6

The rheostat controls which of the following in the filament current?
A. Voltage
B. Current
C. Resistance
D. Temp

Answer 6

C. Resistance

Question 7

The timer circuit (exposure timer) is typically located where?
A. Secondary side of the filament circuit
B. Primary side of the tube circuit
C. Primary side of the filament circuit
D. Primary side of the autotransformer
E. Secondary side of the tube circuit

Answer 7

B. Primary side of the tube circuit

Question 8

The tech has direct control of the resistance in the filament circuit through which setting on the control panel?
A. AEC
B. kV selector
C. mA station
D. Focal spot selector

Answer 8

C. mA station

Question 9

When the negative half of each AC cycle is suppressed we are left with which of the following?
A. Single-phase half wave
B. 3-phase 6 pulse
C. Single-phase full wave
D. 3-phase 12 pulse

Answer 9

A. Single-phase half wave

Question 10

Which exposure timer is based on how fast a motor turns a shaft?
A. Electronic
B. AEC
C. mAs
D. Synchronous

Answer 10

D. Synchronous

Question 11

Which component increases voltage about 500 times?
A. Rheostat
B. Step-up transformer
C. Filament
D. Rectifier

Answer 11

B. Step-up transformer

Question 12

Which component serves to route electricity through the x-ray tube in the same direction each time?
A. Rectifier
B. Step-down transformer
C. Autotransformer
D. Rheostat

Answer 12

A. Rectifier

Question 13

What is the output voltage of a transformer with 30 coils in the primary and 90 coils in the secondary when 120 volts is applied?
A. 1
B. 12
C. 40
D. 360

Answer 13

D. 360

Question 14

Which of the following technique settings will have the highest resistance in the filament circuit?
A. 90 kV @ 100 mA
B. 70 kV @ 10 mA
C. 100 kV @ 1000 mA
D. 90 kV @ 50 mA

Answer 14

B. 70 kV @ 10 mA

Question 15

What characteristic of AC is important to transformer operation?
A. Fluctuating magnetic field
B. Steady current strength
C. Easier to control
D. Higher voltage

Answer 15

A. Fluctuating magnetic field

Question 16

The step-down transformer is a part of which circuit?
A. Secondary (high-voltage)
B. Filament
C. Primary
D. Circuit breaker

Answer 16

B. Filament

Question 17

A step-down transformer is used in the filament current for what purpose?
A. Improve tube efficiency
B. Decrease current to the filament
C. Protect the filament by decreasing voltage
D. Create kV for the filament

Answer 17

C. Protect the filament by decreasing voltage

Question 18

The step-up transformer serves what purpose in the general x-ray circuit?
A. Decreases voltage applied to the x-ray tube
B. Increases voltage to kV needed for x-ray production
C. Improves the efficiency of the current
D. Protects the x-ray circuit from overload

Answer 18

B. Increases voltage to kV needed for x-ray production

Question 19

The process by which a transformer increases or decreases voltage is called:
A. Magnetic flux
B. Line compensation
C. Mutual induction
D. Alternating current

Answer 19

C. Mutual induction

Question 20

Why are rectifiers necessary in the general x-ray circuit?
A. To improve efficiency of the circuit
B. To increase voltage to the x-ray tube
C. To protect the circuit against power surges
D. Because the tube operates best when current flows from anode to cathode

Answer 20

D. Because the tube operates best when current flows from anode to cathode

Question 21

With 4 rectifiers and 1 waveform, what is the voltage ripple?
A. 100%
B. 13%
C. 1%
D. 3.5%

Answer 21

A. 100%

Question 22

What is the primary limitation of the stationary anode?
A. Too large
B. Too many x-rays produced
C. Heat capacity
D. Too slow

Answer 22

C. Heat capacity

Question 23

There is a risk of burns from touching an x-ray tube housing.
True or False

Answer 23

True

Question 24

The glass envelope of the x-ray tube is made of Pyrex to:
A. Withstand high temperatures
B. Provide a source of electrons
C. Avoid easy breakage of glass
D. Help cool the tube

Answer 24

A. Withstand high temperatures

Question 25

The protective housing serves as an electrical insulator. True or False

Answer 25

True

Question 26

How does the focusing cup "focus" electrons on the anode? A. By electrostatic repulsion B. By focusing them through a narrow port C. By emitting them one by one D. By using a lens system

Answer 26

A. By electrostatic repulsion

Question 27

Tanning or darkening of the tube is a result of: A. Vaporized tungsten B. Arcing of the tube C. Loss of a vacuum D. Heat exposure

Answer 27

A. Vaporized tungsten

Question 28

By rotating an anode disc, we are able to spread heat over a larger surface area. True or False

Answer 28

True

Question 29

The housing serves as a thermal cushion by: A. Cooling the tube B. Stabilizing the tube C. Slowing rotation speed D. Maintaining a vacuum

Answer 29

A. Cooling the tube

Question 30

One of the roles of the anode is to: A. Provide a reservoir of electrons B. Give filament electrons kinetic energy C. Cool the tube D. Hold a negative charge

Answer 30

B. Give filament electrons kinetic energy

Question 31

What is added to the filament to increase thermionic emission? A. Rhenium B. Molybdenum C. Aluminum D. Thorium

Answer 31

D. Thorium

Question 32

What is the purpose of the target window of the glass envelope? A. Remove undesirable x-rays from the beam B. Add electrons to filament stream C. Help cool the tube D. Minimize interference with x-rays leaving the tube

Answer 32

D. Minimize interference with x-rays leaving the tube

Question 33

Which target angle will produce the smallest effective focal spot? A. 10 B. 12 C. 17 D. 7

Answer 33

D. 7

Question 34

Rectifiers serve to do which of the following? A. Route electricity through tube the same way B. Convert voltage to kilovoltage C. Protect tube from overload D. Help cool the tube

Answer 34

A. Route electricity through tube the same way

Question 35

What metal do we use as the target because of its atomic complexity? A. Lead B. Copper C. Aluminum D. Tungsten

Answer 35

D. Tungsten

Question 36

Why do we limit the smaller filaments to the lower mA stations? A. Less heat produced with smaller stations & techniques B. Faster exposures C. Easier to design this way D. Greater x-ray production

Answer 36

A. Less heat produced with smaller stations & techniques

Question 37

Most of the energy used to produce x-rays results in which of the following? A. X-Rays B. Protons C. Electrons D. Heat

Answer 37

D. Heat

Question 38

Small changes in filament current will cause large changes in tube current. True or False

Answer 38

True

Question 39

The 2 major components of the cathode are within the glass envelope. True or False

Answer 39

True

Question 40

The force of attraction between the anode and filament electrons is so strong that the electrons reach 1/2 the speed of light. True or False

Answer 40

True

Question 41

By what method is the rotor of the x-ray tube turned? A. Self-induction B. Mutual Induction C. The rotor does not move D. Mechanical Rotation

Answer 41

B. Mutual Induction