1 x-rays

Question 1

eV

Answer 1

kinetic E gained

Question 2

J

Answer 2

E unit

Question 3

voltage

Answer 3

causes e- to move

Question 4

power

Answer 4

rate of E use (J/sec)

Question 5

Z

Answer 5

atomic # (# of protons)

Question 6

A

Answer 6

mass # (protons + neutrons)

Question 7

electromagnetic radiation

Answer 7

oscillating electric & magnetic fields

Question 8

frequency (f)

Answer 8

cycles/sec (Hz)

Question 9

velocity (v)

Answer 9

f x wavelength

Question 10

photon energy is proportional to ___.

Answer 10

frequency

Question 11

gamma rays

Answer 11

high E e- from nuclear process

Question 12

transformer

Answer 12

increases voltage by orders of magnitude

Question 13

typical transformer ratings (kV, mA, kW)

Answer 13

100kV, 100 kW, 1000 mA

Question 14

rectifier

Answer 14

changes current from alternating to direct (AC -> DC)

Question 15

mA

Answer 15

tube current flowing through the x-ray tube

Question 16

brems. xrays

Answer 16

energetic e- made when e- interact with nuclear electric fields

Question 17

relationship btwn focal spot & blurring?

Answer 17

small fs –> decreased blurring

Question 18

relationship btwn focal spot & exposure time?

Answer 18

large fs –> decreased exposure time bc tolerates more power loading

Question 19

how to change kV & target Z to increase brems xray production?

Answer 19

increase accelerating kV increase Z of target

Question 20

what are the 3 fates of xrays

Answer 20

1/3 scatter 2/3 absorption <1% transmitted/penetration

Question 21

define the 2 types of scatter

Answer 21

1. Compton: most e-, photons transfers E to a Compton e- 2. Coherent: low E e- is scattered from an atom without any E loss; <5% of scatter.

Question 22

Molybdenum keV & Z

Answer 22

20 keV Z=42

Question 23

Tungsten keV & Z

Answer 23

70 keV Z=74