Chapter 2 from Worksheets

Question 1

What type of glass is used for a x-ray tube?

Answer 1

PYREX

Question 2

If a tube operates at 70 kV or above, what is the amount of filtration it must possess?

Answer 2

2.5mm of Al. (or it’s equivalent)

Question 3

When electrons strike anode what percent is heat?

Answer 3

99%

Question 4

When electrons strike anode what percent is x-ray?

Answer 4

1%

Question 5

The majority of the x-ray beam is created through a process called what?

Answer 5

Bremsstrahlung

Question 6

Minority of the x-ray beam is created through a process called?

Answer 6

Characteristic

Question 7

A dual focus tube has what

Answer 7

2 filaments/cathodes and 1 anode

Question 8

Leakage from and x-ray tube cannot exceed…..

Answer 8

100mR/hr @ 1 meter

Question 9

The average anode rotates….

Answer 9

3,000-10,000rpm

Question 10

The cathode possesses what type of charge?

Answer 10

negative

Question 11

The anode possesses what kind of charge?

Answer 11

Positive

Question 12

What type of rotor rotates the anode?

Answer 12

Induction

Question 13

The projected or effective focal spot is smaller than the AFS

Answer 13

Line focus principle

Question 14

What 2 purposes does the glass envelope serve in the xray tube?

Answer 14

A. Insulation from electrical shock

B. Dissipates heat

Question 15

Below 69kV, 100% of the xray beam is the result of

Answer 15

Brem’s radiation

Question 16

When electrons drop for outer shell to fill holes in inner shells

Answer 16

Characteristic Radiation

Question 17

When electrons approach target of atom and rapidly decelerate and change direction

Answer 17

Bremsstrahlung “Braking”

Question 18

Many energies in a beam (not all same)

Answer 18

Polyenergetic

Question 19

What type of metal can be added to the anode to make it lighter and able to withstand great amounts of heat?

Answer 19

Graphite

Question 20

“Cut Off” point in technique that would cause you to select a large focal spot?

Answer 20

100mAs

Question 21

If you select a large focal spot what do you sacrifice?

Answer 21

Detail

Question 22

Unit of frequency?

Answer 22

Hz

Question 23

Steeper anode angle will result in

Answer 23

Better Detail

Question 24

Intensity of the xray beam is greater on which side?

Answer 24

Cathode side of tube

Question 25

Three heat unit equations

Answer 25

1. Single Phase
2. Three Phase
3. High Frequency

Question 26

Single Phase Equation

Answer 26

(mA)(time)(kV)

Question 27

Three Phase Equation

Answer 27

(mA)(time)(kV)(1.35)

Question 28

High Frequency Phase Equation

Answer 28

(mA)(time)(kV)(1.40)

Question 29

If too high heat units are being produced how do you fix it and still maintain detail?

Answer 29

Decrease mAs and increase kV

Question 30

If you decrease kV then what do you do to mAs?

Answer 30

DOUBLE it

Question 31

If you increase kV then you do what to mAs?

Answer 31

cut in half

Question 32

Do not hold down rotor button without making an exposure

Answer 32

Don’t Boost and Hold

Question 33

Amount of filtration that reduces intensity of beam to half its original value

Answer 33

Half-Value Layer

Question 34

When performing an AP projection of the thoracic spine, in order to use the Anode Heel Effect to your advantage; you should place the cathode end of tube over which aspect of spine?

Answer 34

Inferior

Question 35

Main purpose of filtration

Answer 35

Decrease Patient’s Skin Dose

Question 36

Three ways to enhance anode heel effect?

Answer 36

1. steep/small anode angle
2. short SID
3. Large IR

Question 37

Total Filtration=

Answer 37

ADD+INHERENT

Question 38

2.5mm+

Answer 38

2.0+0.5

Question 39

X-Ray of part with different thicknesses or compensation for air filled lungs

Answer 39

When To Use Wedge Filters