Formulas

Question 1

Do grids decrease production of scatter?

Answer 1

No! They reduce amount of scatter reaching the IR

Question 2

Scatter is what?

Answer 2

Density

Question 3

Grid ratio

Answer 3

Height of pb strips/ distance between pb strips

Question 4

When dealimg with grids, you what on the left/ old side

Answer 4

Divide

Question 5

What do you do on the right/new side with a grid

Answer 5

Multiply

Question 6

Conversion factor for 5:1

Answer 6

2

Question 7

6:1

Answer 7

3

Question 8

8:1

Answer 8

4

Question 9

12:1

Answer 9

5

Question 10

16:1

Answer 10

6

Question 11

Screens: every time you double the SS you do what to the mAs?

Answer 11

Cut it in half

Question 12

Cut screen speed in half you do what to mAs?

Answer 12

Double it

Question 13

Increased screen speed=?

Answer 13

Decreased pt dose, and detail

Question 14

Decreased screen speed=?

Answer 14

Increased pt dose and detail

Question 15

Inverse square law

Answer 15

Old mAs/ new mAs= old distance (sq)/ new distance (sq)

Question 16

Double distance and SID =?

Answer 16

Exposure will be 1/4 as strong

Question 17

Cut distance and SID in half=?

Answer 17

Exposure will be 4x stronger

Question 18

Above 90 kv: kv increased by 15, you do what?

Answer 18

Cut mAs in half

Question 19

Above 90 kv: kv decreased by 15

Answer 19

Double mAs

Question 20

Below 90 kv: if its encreased by what? You cut mas half

Answer 20

10 kv

Question 21

Kv decreases by 10 when below 90 kv you do what?

Answer 21

Double mas

Question 22

Kvp controls:

Answer 22

Contrast, scatter, lattitude

Question 23

mAs controls:

Answer 23

Density, pt dose

Question 24

To see a visible change in density you must….

Answer 24

Increase mAs by 30%

Question 25

mAs=

Answer 25

mA x time

Question 26

mA=

Answer 26

mAs/time

Question 27

Time=

Answer 27

mAs/mA