Physics

Question 1

Who discovered Xray? and when?

Answer 1

Dr. Wilhelm Conrad Roentgen

November 8th 1895

Question 2

Velocity

Answer 2

V=D/T

Question 3

Roentgen (R)

Answer 3

is used to quantify radiation intensity

Question 4

Rad/ Grey

Answer 4

is used to quantify the biologic effects of radiation on humans and animals. aka absorbed dose.
1rad= 10^-2Gy (.01 Gy)

Question 5

Rem

Answer 5

this is used to quantify occupational exposure or dos equivalent
1rem=10^-2Sv (.01Sv)

Question 6

Curie

Answer 6

is used to quantify radioactivity

Question 7

Anode

Answer 7

is the positive electrode in the X-ray tube. this part is over the head of the table

Question 8

cathode

Answer 8

is the negative electrode in the X-ray tube. this section is usually at the foot of the table.

Question 9

Atom

Answer 9

basic building block of matter

consists of protons, neutrons, electrons and the nucleus

Question 10

Effective focal spot

Answer 10

the X-ray beam area as seen from the perspective of the patient

Question 11

electromagnetic radiation

Answer 11

an electric and magnetic disturbance traveling through space at the speed of light

Question 12

emulsion

Answer 12

the radiation-sensitive and light sensitive layer of the film

Question 13

Remnant radiation

Answer 13

aka exit radiation: the attenuated X-ray beam leave the patient and is composed of both transmitted and scattered radiation.

Question 14

Fluorescence

Answer 14

refers to the ability of phosphors to emit visible light only while exposed to X-rays

Question 15

Flux Gain

Answer 15

an expression of the ratio of the number of light photons to the number of light photons emitted input phosphor

Question 16

Focal Plane

Answer 16

same as the object plane, the plane where the area of interest lies at the level of the fulcrum

Question 17

what will impact the viability

the anode heel effect

Answer 17

SID and IR size

Question 18

inverse square law

Answer 18

I1/I2=(D2)^2/(D1)^2

Question 19

Pixel Pitch

Answer 19

Pixel size and spacing determine the spatial resolution of the digital image. This is known as:

Question 20

acute radiation syndrome

Answer 20

a whole-body dose in a short period of time, certain symptoms will occur; these are referred to as

Question 21

Backscatter on a digital image can cause an artifact called a?

Answer 21

Phantom image artifact

Question 22

To eject a K-shell electron from a tungsten atom, the incoming electron must have an energy of at least

Answer 22

70 KeV

Question 23

The tabletop exposure rate during fluoroscopy shall not exceed

Answer 23

10 R/min

Question 24

Bremsstrahlung Radiation

Answer 24

Bremsstrahlung (Brems) or “braking” x-ray production, a high-speed electron, accelerated toward a tungsten atom, is attracted (and “braked,” that is, slowed down) by the positively charged nucleus and therefore is deflected from its original course with a resulting loss of energy. This energy loss is given up in the form of an x-ray photon

Question 25

A star pattern is used to measure

Answer 25

focal spot resolution

Question 26

15% rule

Answer 26

Increase density= kvp x 1.15
Decrease density= kvp x .85
Maintain density= kvp x 1.15 and mAs/2

Question 27

densitometer.

Answer 27

The instrument that is used frequently in quality-control programs to measure varying degrees of x-ray exposure

Question 28

An exposed image plate will retain its original image quality for about…?

Answer 28

8 hours

Question 29

Most common used types of AEC devices

Answer 29

Ion chamber and photomultiplier tube

Question 30

Light sensitive AEC devices are known as

Answer 30

Phototimers