Physics 2/14

Question 1

So those are good test question would be if I gave you a list of electromagnetic or particulate radiation,
which I’m going to show you here in a second, be able to distinguish the difference.

Question 2

properties of electromagnetic radiation:

test question

Answer 2

no weight, no mass
no electrical charge
travels at speed of light
travels as both particle and wave
goes in straight line
have a different measurable energies (frequencies and wavelength)

Question 3

particulate radiation:

Answer 3

alpha particles, beta particles, fission fragments.

Question 4

amperage:

Answer 4

number of electrons flowing in a wire / second

how many

Question 5

Voltage:

Answer 5

electrical pressure pushing electrons through a wire.

how hard we are pushing it

Question 6

alternating current (AC)

Answer 6

electron going back and forth

Question 7

Thermionic emmision:

Answer 7

The boiling off of electrons to create light and a cloud of electrons around the filament.

Question 8

anode vs cathode

where are x rays produced / electrons produced?

Answer 8

Anode (tungsten target): x rays made here
Cathode (tungsten filament side, with molybdenum cup): electrons produced here

Question 9

step down transformer

Question 10

in order to increase how many x rays produced, what do you do?

quantity

Answer 10

increase mA (miliamps)

Question 11

step up transformer

Answer 11

anode

Question 12

in order to increase x ray quality, what do you do?

quality

Answer 12

increase kV

Question 13

penumbra:

Answer 13

focus of the image around the edges, the fuzzy part. No good

smaller focal spot size = less penumbra
larger focal spot size = larger penumbra

Question 14

Line focus principle

on test:

Answer 14

relationship between the anode target angle and the effective focal spot size

the degree of angle placed on the anode target directly effects the effective focal spot size

Question 15

General (bremsstrahlung) radiation

Answer 15

70% of x-rays produced at anode

breaking radiation: as bombarding electron hits nucleus, goes at an angle and generates radiation.

bombarding electron comes fairly close to nucleus, angle changes, radiation released. can hit another tungsten atom and do this again.

Question 16

characteristic radiation

Answer 16

bombarding electron interacts with inner shell electron, knocking it out. outer shells fill inner orbitals, energy released.

below 70 kVp, no characteristic radiation

Question 17

High kVp technique:
Low kVp technique:

Answer 17

high kVp technique : low contrast : best for PERIO diagnosis
Low kVp technique: high contrast: best for CARIES diagnosis

Question 18

inverse square law:

Answer 18

when you double distance from x ray tube from anode to receptor, the dose is much less (inverse square) than the starting distance.

Question 19

Formula of inverse square law:

Answer 19

(Original intensity)/(New Intensity) = (New Distance)^2 / (Original Distance)^2