Ch.15 kVp

Question 0

kVp is the ____ in the high voltage circuit.

Answer 0

Auto transformer

Question 1

Describe kVp.

Answer 1

• A measure of electrical force or pressure behind a current
• Causes electric current flow
• Is a measure of electrical energy(kev)

Question 2

The extreme ___ and ____ of the X-ray tube cause the current to flow.

Answer 2

Negative cathode and positive anode

Question 3

How is kVp measured?

Answer 3

The greater the potential difference of negative to positive then there is more pressure exerted on the electrons to flow this causing greater energy pushing the current and higher kVp will be measured

Question 4

It is necessary to measure kVp at its____ because of its constantly changing kVp on a sine wave.

Answer 4

Average

Question 5

KVp sets the what?

Answer 5

Penetration level

Question 6

What is the most important function of the kVp?

Answer 6

To provide at least partial penetration through all tissues to be recorded

Question 7

The minimum kVp for a particular body part Is defined as?

Answer 7

The lowest kVp that still provides some degree of penetration through all tissues of interest

Question 8

What are 2 determining factors for minimum kVp to use?

Answer 8

Part thickness

Predominant type of tissue

Question 9

Describe the 15% rule.

Answer 9

A 15% increase is kVp is equivalent to an increase of mAs by 50% or overall density of 50%

Question 10

Why do we use the 15% rule?

Answer 10

Increasing kVp instead of mAs means less dose to the patient