Ch.8 X-ray Machines

Question 1

The main circuit of an x-ray machine is made up of what 3 general sections?

Answer 1

1. control console
2. high-voltage section
3. x-ray tube

Question 2

What 3 components make up the control console?

Answer 2

1. incoming lines and power switch
2. exposure switch and timer
3. autotransformer for kVp selection

Question 3

What 4 components make up the high voltage section?

Answer 3

1. pre-reading kVp meter
2. step-up transformer for high voltage
3. mA meter
4. rectification bridge

Question 4

What 2 components make up the x-ray tube?

Answer 4

1. x-ray tube
2. bank of resistors for mA selection
3. step-down transformer

Question 5

The kVp major and kVp minor controls on the X-ray tube set what?

Answer 5

set the autotransformer

Question 6

What is the difference between AC waves and electromagnetic waves?

Answer 6

amplitude which indicates increased voltage

Question 7

Any meter connected in series will count the rate of electrons passing through and measures______.

Answer 7

Amperage

Question 8

Any meter connected in parallel will compare potential difference between two wires and measure______.

Answer 8

Voltage

Question 9

____ _____ ____ compensates for fluctuations in incoming voltage so that radiographic techniques can be consistent.

Answer 9

Line voltage compensators

Question 10

Line voltage compensators guarantee what?

Answer 10

a constant value of voltage

Question 11

This is the first major circuit in the x-ray tube circuit.

Answer 11

autotransformer

Question 12

Incoming line voltage X Autotransformer turns ratio= what?

Answer 12

Autotransformer output voltage

Question 13

Autotransformer output Voltage X step-up transformer turns ratio= what?

Answer 13

Final output of voltage across the tube electrodes

Question 14

kVp selects a series of ____ which adjust the number of turns on the secondary coil.

Answer 14

taps

Question 15

The boiling off of electrons is known as?

Answer 15

Thermionic emission

Question 16

The process of thermionic emission frees electrons from the filament wire _____ to exposure which greatly improves efficiency. (Prior, after)

Answer 16

Prior

Question 17

For thermionic emission to occur the filament wire has to be brought to what?

Answer 17

An extremely hot temperature

Question 18

We use high _____ to heat the filament wire.

Answer 18

Amperage

Question 19

Using high amperage to heat the filament wire causes millions more electrons trying to crowd their way through the filament thus causing great _____, due to the wire being thinner than regular electric wire.

Answer 19

Friction

Question 20

With high amperage current entering the thin filament the electrons jostle and bump into each other so much that a tremendous amount of _____ is produced which ____ the wire.

Answer 20

Friction, heat

Question 21

There are two currents that enter the filament, one designed to heat it using high____ and a later one with high_____ to produce the actual exposure.

Answer 21

Amperage, voltage

Question 22

The high amperage current used to heat the filament is applied whenever the ____ button is held down at the console.

Answer 22

Rotor

Question 23

The filament must be brought up to the full temperature corresponding to the ____ station that has been selected.

Answer 23

mA

Question 24

The anode is connected to the ____ of an AC motor.

Answer 24

Rotor

Question 25

The filament is heated in a _____ circuit.

Answer 25

Filament

Question 26

The filament circuit must be seperate from the main circuit because both high voltage and high amperage cannot be produced in the same circuit since there is a limited amount of ____ power available.

Answer 26

Electrical

Question 27

A __-____ transformer must be in the filament circuit.

Answer 27

Step down transformer

Question 28

The turns ratio in the step down transformer of the filament circuit is? And produces how many amps to heat the wire enough for thermionic emission to occur?

Answer 28

1:44, 5 amps

Question 29

The effect of a 1:44 turns ratio is to divide the incoming ____ from 220 down to 5___.

Answer 29

Voltage, volts

Question 30

With a turns ratio of 1:44 in a filament circuit the amperage is multiplied by a factor of? Which produces enough current to heat the wire.

Answer 30

44

Question 31

When you select an mA station, an electrical ____ in the filament circuit makes contact with a particular electronic resistor.

Answer 31

Taps

Question 32

By Ohms law when the voltage is fixed, as the resistance increases, the amperage_____.

Answer 32

Decreases

Question 33

What is the formula used with the filament circuit based on Ohms law?

Answer 33

220v= IR

Question 34

What are the 4 types of exposure timers?

Answer 34

1. Synchronized
2. Electronic
3. mAs
4. AEC

Question 35

The ____ timer allows for the wide range of time intervals. It is the most sophisticated, complicated, and accurate.

Answer 35

Electronic

Question 36

Electronic timers are based on the time it takes to fully charge a special _____ through different amounts of electrical resistance.

Answer 36

Capacitor

Question 37

Once the capacitors limit is reached a surge of electricity is allowed to run off from it. This pulse of electrons charges an electromagnet that pulls open the ____ switch, shutting off the exposure.

Answer 37

Exposure

Question 38

On an electronic timer the longer the exposure time then the more resistance and the current goes___. ( up or down)

Answer 38

Down

Question 39

On an electronic timer if the time is short, then resistance is low and the current goes___ ( up or down)

Answer 39

Up

Question 40

In the capacitor of the electronic timer the current and resistance are _____ proportional.

Answer 40

Inversely proportional

The greater the resistance the less the current