Ch 1 Flashcards Preview

Flashcards in Ch 1 Deck (18)
1
Q
```Milliamperage seconds (number of electrons and number of x-rays)
mA x time```
A

mAs

2
Q

Source to image receptor (as far back as possible)

A

SID

3
Q

Object to IR distance
Always want object as close to IR as possible otherwise magnification distortion occurs (ex: shadow)
Want heart closer to IR

A

OID

4
Q

Kilovoltage peak (penetrating ability of x-rays)

A

kVp

5
Q

One thousandth of the unit to which it’s joined

A

Milli

6
Q

1/1000 ampere (1000 mA = 1 A)

A

Milliampere

7
Q

1/1000 second (1000 ms = 1 s)

A

Millisecond

8
Q

1/1000 meter (1000 mm = 1 m)

A

Millimeter

9
Q

An amount 1000 times the unit to which it’s joined

A

Kilo

10
Q

1000 volts

A

Kilovolt

11
Q

1000 grams

A

Kilogram

12
Q

Intensity of the beam is “inversely” proportional to the “square of the distance”
Intensity of the beam decreases by 4 when the distance is doubled and is increased by 4 when the distance is halved
I1/I2=D2^2/D1^2

A

Inverse square law

13
Q

Formula used when changing distances (SID)
Directly proportional
mAs1/mAs2=D1^2/D2^2

A

Exposure/density maintenance formula

14
Q

Similar triangles formula

A

b/B=h/H

15
Q

What does b in similar triangles formula represent?

A

Base of small triangle (object)

16
Q

What does B in similar triangles formula represent?

A

Base of big triangle (IR)

17
Q

What does h in similar triangles formula represent?

A

Height of small triangle (distance from object to source)

18
Q

What does H in similar triangles formula represent?

A

Height of big triangle (SID)