Bremsstrahlung x-rays

Question 1

What does Bremsstrahlung mean in German?

Answer 1

“slowed down radiation”
“braking radiation”

Question 2

Bremsstrahlung x-rays vary from ____ energy (keV) x-rays up to the _____ energy of the kVp selected.

Answer 2

low; peak

Question 3

Bremsstrahlung radiation is created within the x-ray tube when high-energy electrons interact with which of the following?

A. outer shell electrons
B. shell electrons
C. electric field of the nucleus
D. nuclear force of the nucleus

Answer 3

C. electric field of the nucleus

Question 4

The maximum energy of a bremsstrahlung photon that can be created during an x-ray exposure is equal to the:

Answer 4

energy of the incident electron

Question 5

What percentage do Bremsstrahlung x-rays make up of the primary x-ray beam?

Answer 5

90%

Question 6

What is being slowed down in Brems x-rays?

Answer 6

the incident electron coming from the cathode

Question 7

Is the radiation (x-ray photon) being slowed down?

Answer 7

no

Question 8

T/F: x-ray photons do not speed up or slow down

Answer 8

true

Question 9

The maximum energy of bremsstrahlung photons is controlled by what technical factor?

Answer 9

tube potential (kVp)

Question 10

The production of a bremsstrahlung photon involves an interaction between an incident electron and what else?

Answer 10

the nucleus of a tungsten atom

Question 11

The energy of a bremsstrahlung photon is dependent on which two variables?

Answer 11

energy of the incident electron

proximity of the incident electron to the nucleus

Question 12

What happens when electrons change direction while being drawn towards the nucleus?

Answer 12

they are forced to slow down to “make the turn”
(like a car)

Question 13

The energy of a bremsstrahlung x-ray photon is equal to the:

Answer 13

difference between the incoming and outgoing electron energy

Question 14

When the electrons slow down, what happens?

Answer 14

they give up some of their energy in the form of x-rays

Question 15

What does the Law of Conservation of Energy state?

Answer 15

energy cannot be created or destroyed

Question 16

What does the “skid mark” on the street represent during bremsstrahlung photon production?

Answer 16

the x-ray photon

Question 17

energy spent as heat to create x-ray photon + final kinetic energy of incident electron after turning toward nucleus =

Answer 17

original kinetic energy of incident electron

Question 18

Original keV of incident electron =

Answer 18

keV of Brems x-ray photon + keV of electron after nucleus interaction

Question 19

During an x-ray exposure, an incident electron strikes the anode with an energy of 84 keV and passes very close to the tungsten nucleus. What is the approx. energy of this electron as it exits the atom?

Answer 19

1 keV

Question 20

During an x-ray exposure, an incident electron strikes the anode with an energy of 110 keV and passes very close to the tungsten nucleus. What is the approx. energy of the photon created by this interaction?

Answer 20

110 keV

Question 21

the sharper the turn:

Answer 21

the higher the energy photon produced

Question 22

high keV = high quality =

Answer 22

higher penetration

Question 23

how much the electron will slow down depends on:

Answer 23

how close the electron comes to the nucleus of tungsten atom

this also determines the keV of the resulting x-ray

Question 24

An x-ray imaging system at 70 kVp can produce electrons with kinetic energies from zero to 70 keV

Answer 24

true

Question 25

T/F: most x-rays are bremsstrahlung x-rays

Answer 25

true

Question 26

Bremsstrahlung x-ray production is responsible for the _________________ nature of the x-ray beam

Answer 26

polyenergetic

Question 27

What would very low energy brems x-rays not do?

Answer 27

penetrate further than the patient’s skin

contribute to image formation

(would be a bad x-ray)

Question 28

What do very low energy brems x-rays contribute to?

Answer 28

patient skin dose

Question 29

How do we deal with low energy brems x-ray photons that will not contribute to a diagnostic radiograph and only increase patient dose?

Answer 29

filtration

Question 30

What does filtration create?

Answer 30

a more monoenergetic and harder average beam

Question 31

Increasing filtration increases:

Answer 31

the AVERAGE quality of an x-ray beam

Question 32

Increasing filtration decreases:

Answer 32

quantity (intensity) of x-ray beam