# Endterm Flashcards

1
Q

Electromagnetic induction and voltage transformation, its function is to provide current at high voltage to the x-ray tube

A

X-ray generator

2
Q

electrical power available in the hopsital or clinic provided up to?

A

480V

3
Q

Much __ than 20,000 to 150,000 needed for x-ray production

A

Lower

4
Q

__ are principle components of x-ray generators they convert low voltage to high voltage through a process called __

A

Transformers, electromagnetic induction

5
Q

Effect that occurs with changing magnetic field and alternating electrical current, a reciprocal between electric and magnetic field

A

Electromagnetic induction

6
Q

Performs task of transforming alternating input voltage to alternating output voltage using principle of electromagnetic induction

A

Transformers

7
Q

Input ac power (voltage and current) produced?

A

Oscillating electrical and magnetic field

8
Q

One insulated wire wrapping (primary winding) carries the__ other insulated wire wrapping (secondary winding) carries

A

Input load (primary voltage and current), induced output load (secondary voltage and current)

9
Q

Primary and secondary windings are electrically but not __ isolated by insulated wires

A

Magnetically

10
Q

Secondary windings are bathed in the?

A

Oscillating magnetic field

11
Q

Ns is?

A

Seconday coil

12
Q

Np is?

A

Primary coil

13
Q

Vs is

A

Alternating input

14
Q

Vp is?

A

Alternating output

15
Q

Ns > np

A

Step up transformer

16
Q

Ns<np

A

Step down transformer

17
Q

Ns=np

A

Isolation

18
Q

Is the ratio of energy production of expenditure per unit of time

A

Power

19
Q

__ unit of power is __

A

51, watt (W)

20
Q

The high-voltage section of an x-ray generator
contains a step-up transformer, typically with a
primary-to-secondary turns ratio of ?

A

1:500 to 1: 1,000.

21
Q

Within this range, a tube voltage of __ requires
an input peak voltage of __ to __, respectively.

A

100 kVp, 200V, 100V

22
Q

Is the electrical potential of earth. center tapping to ground does not affect the maximum voltage at any point in the circuit relative to the ground to 1/2 of peak voltage applied to the tube.

A

Ground potential

23
Q

Maximum voltage st any point in the circuit for a center-tapped transformer of?

A

150 kVp is -75 kVp or + 75 kVp

24
Q

Low kVp (__) used in mammography does not present a big electrical insulation problem

A

Less than 50 kVp

25
Q

Consist of a single coil wire wrapped around an iron core. It has fixed number of turns, two lines on the input side and two lines on the output side

A

Autotransformers

26
Q

Autotransformers operates on the principal of?

A

Self induction

27
Q

Standard transformer operates on the principle of?

A

Mutual induction

28
Q

Permits much larger increase/decrease in voltage and it electrically isolates primary from secondary circuits

A

Standard transformer

29
Q

Has a number of taps on input and output sided to permit small incremental increase/decrease in output voltage

A

Switching autotransformers

30
Q

X-ray tube provides an environment for x-ray production via?

A

31
Q

Major components of x-ray tube

A

Cathode, anode, rotor,stator, glass(metal envelope), and tube housing

32
Q

__ is the rate of electron flow from cathode to anode measured in __ where 1 mA = __

A

Tube current, milliamperes, 6.24X1015 electrons/sec

33
Q

__ is used to adjust kVp produced by xray generator

A

Switched autotransformers

34
Q

__ is provided to the input side of autotransformers and __ of the autotransformers is provided to the primary side of __

A

Standard alternating current, output voltage, high voltage transformer

35
Q

For continuous fluoroscopy the tube current is typically _ to _

A

1-5 mA

36
Q

For projection radiography tube currents from __ to __ mA are used with short exposure time (less than __msec)

A

100,1000, 100

37
Q

Three major selectable parameters on x-ray generator control panel that determine the x-ray beam characteristic (quality and quantity)

A

kVp, mA and exposure

38
Q

The sources of electron in the x-ray tube is the __ which is a helical filament of tungsten wire surrounded by a __

A

Cathode, focusing cup

39
Q

This structure is electrically connected to the __

A

Filament circuit

40
Q

The filament circuit provides a voltage up to __ to the filament, producing a current up to about __ through the filament.

A

10 V, 7 A

41
Q

Electrical resistance heats the filament and releases electrons via a process called?

A

Thermionic emission

42
Q

For diagnostic imaging, electrons from cathode filament are accelerated towards anode by a peak voltage ranging from __ to __ V (__ to__ kVp)

A

20,000 to 150,000 V (20 to 150 kVp)