Lecture #2 Flashcards Preview

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Flashcards in Lecture #2 Deck (21):
1

High E Bremsstrahlung

e- directly collide with nucleus

2

Med E Bremsstrahlung

e- pass close to nucleus

3

Low E Bremsstrahlung

e- pass a far distance from nucleus

4

Characteristic Radiation... What is it?

high speed e- hits another e- and knocks it out of orbit

5

What is found at the Cathode?

- charge
Tungsten filament
focusing cup

6

What is found at the Anode?

+ charge
Tungsten target
Copper stem

7

What does placing a target at an angle provide?

Smaller effective focal spot for a sharp image

8

Low V tube current

Heats the tube filament and makes an e- cloud

9

High tube V

accelerates the e- stream

10

Step-Down Filament Transformer

Used to reduce voltage and heat the filament

11

Step-Up Transformer

Increase V to speed up electrical force

12

Auto - Transformer

controls the Step-Up transformer to get the desired kVp

13

What is the most frequent source of malfunction in X-ray tubes?

Filament burnout

14

What is directly proportional to the tube current?

Quantity of radiation

15

when tube current (ma) increases then....

More e- are released to the target

16

increase in kVp causes

and increase in x-ray penetration of matter

17

Why are aluminum filters used?

to absorb low E phtons

18

What is a Collimator?

a metal tube used to reduce the size of the x-ray

19

Define Coherent Scattering

low E photons are deflected by out ring e-
Causes "foggy film"

20

Define Compton Scattering

Occurs when a photon hits an e- and it is shot off
Causes darken images

21

What is Beam Attenuation?

Low E photons are more readily absorbed compared to High E photons