physics chapters 5-6
Help!
|
|
||||
|---|---|---|---|---|---|
| What are the 3 major parts of the xray circuit? | 1.Low voltage operating console
2.High voltage generator
3.xray tube
🗑
|
||||
| What type of transformers are use in the xray circuit? | Autotransfomer, step up transformer, step down (filament) transformer
🗑
|
||||
| What kind of timer is used in the xray circuit? | electronic timer
🗑
|
||||
| What does a rectifier do? | coverts AC to DC
🗑
|
||||
| how many rectifiers does single phase, half-wave use? | 2 rectifiers
🗑
|
||||
| how many rectifiers does single phase, full-wave use? | 4 rectifiers
🗑
|
||||
| how many rectifiers does 3 phase, 6 pulse use? | 6 rectifiers
🗑
|
||||
| how many rectifiers does 3 phase, 12 pulse use? | 12 rectifiers
🗑
|
||||
| What is meant by single phase power? | power that ranges from zero to 120 and results in a pulsating xray beam
🗑
|
||||
| What is meant by 3 phase power? | multiple superimposed voltage wave forms, that results in nearly constant high voltage
🗑
|
||||
| Why is 3 phase more efficient than single phase? | Because it never goes to zero so its power is always constant
🗑
|
||||
| How efficient is a 3 phase, 6 pulse generator? | 87%
🗑
|
||||
| how efficient is a 3 phase, 12 pulse generator? | 96.5%
🗑
|
||||
| How many degrees out of step is each phase? | 120 degrees
🗑
|
||||
| What device is used to check timer accuracy of 3 phase equipment? | solid-state radiation detector
🗑
|
||||
| Explain a high frequency generator? | produces a nearly constant potential voltage waveform, improving image quality with lower pt dose, also very little voltage ripple
🗑
|
||||
| Explain capacitor-discharge generator? | used on portables, stores electricity, then discharges it upon taking an exposure
🗑
|
||||
| what formula is used for power rating for xray units? | watts= mA x kV
KW= (mA x kVp)/1000
(single phase: multiply expression by .7)
🗑
|
||||
| What devices are used for AEC? | -currently= ionization chamber
-orginally= photodiode
🗑
|
||||
| Define isotropic as it relates to the xray beam? | xrays are produced with equal intensity in all directions
🗑
|
||||
| What is the filament made of? | tungsten
🗑
|
||||
| What is meant by dual focus? | 2 filaments and 2 focal spots
🗑
|
||||
| What is the focusing cup made of and what is its function? | tungsten or molybdenum, and it focuses the electrons
🗑
|
||||
| What is meant by thermionic emission? | Is when the current passes thru the filament and literally boils off electrons
🗑
|
||||
| what is filament vaporization? | heating of the tube forms tungsten vapors inside the tube
🗑
|
||||
| What is the more prevalent cause of tube failure? | filament vaporization
🗑
|
||||
| what causes the anode to crack or pit? | excessive temps. during single exposure
🗑
|
||||
| what is the HU (heat unit) equation for single phase? | HU=kV x mAs
🗑
|
||||
| What is the HU equation for 3 phase, 6 pulse? | HU=kV x mAs x 1.35
🗑
|
||||
| what is the HU equation for 3 phase, 12 pulse? | HU=kV x mAs x 1.41
🗑
|
||||
| what is the HU equation for high frequency? | HU=kV x mAs x 1.45
🗑
|
||||
| What are the 2 main circuits of the xray imaging system? | 1.high voltage/tube circuit
2.filament
🗑
|
||||
| what are the typical xray room ranges for kVp and mA? | kVp: 25-120
mA: 100-1200
🗑
|
||||
| What does the line compensator do? | automatically keeps voltage consistent
🗑
|
||||
| What are the electrical connections on the transformers called? | Taps
🗑
|
||||
| what is the equation for the autotransformer law? | Vs/Vp=Ns/Np
🗑
|
||||
| what is the turns ratio equation? | Ns/Np
🗑
|
||||
| When you use AEC the machine sets a back-up timer to what? | 1 and 1/2 times the expected exposure time
🗑
|
||||
| What are the types of timers? | -Mechanical
-Synchronous
-Electronic
-AEC
🗑
|
||||
| If the timer is not working properly it is usually due to what? | faulty rectifior
🗑
|
||||
| what is the maximum permissible level of leakage radiation? | 100 mR/hr at 1m
🗑
|
||||
| what is the space charge effect? | once the electrons boil off they remain in a cloud around the filament
🗑
|
||||
| what are the 2 main parts of the cathode? | filament and focusing cup
🗑
|
||||
| what are the 2 types of anodes? | stationary and rotating
🗑
|
||||
| what are the 3 types of xray tube rating charts? | 1.radiographic rating chart
2.anode cooling chart
3.housing cooling chart
🗑
|
||||
| What is directly connected to the autotransfomer? | kVp meter
🗑
|
||||
|
🗑
|
Review the information in the table. When you are ready to quiz yourself you can hide individual columns or the entire table. Then you can click on the empty cells to reveal the answer. Try to recall what will be displayed before clicking the empty cell.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Created by:
Chrslarsen
Popular Radiology sets