Physics Principles 15% Pt 2

Question 1

How is density related to impedance?
HIGHER DENSITY = _______ IMPEDANCE

Answer 1

Higher impedance!

Question 2

Axial resolution equation= 1/2 ()

Answer 2

Axial resolution = 1/2 (SPL)

Question 3

What media has the highest propagation speed?

Answer 3

BONE= highest propagation speed

Question 4

Increasing the transducer frequency on a multi hertz, transducer will improve _____ resolution in the near and far Field

Answer 4

Axial resolution

Question 5

Decreasing the number of cycles in a pulse will improve what resolution? (Short pulses)

Answer 5

Axial resolution

Question 6

Which of the following imaging parameters (resolution) is responsible for the ability to resolve to separate cysts that are side-by-side in the liver?

Answer 6

Lateral resolution

Question 7

________ resolution is the minimum reflector separation required to produce separate echoes

Answer 7

Spatial resolution

Question 8

DB= _____ of two sound intensity

Answer 8

Ratio

Question 9

What phenomenon is described as the conversion of pressure waves into an electrical voltage?

Answer 9

Piezoelectric effect

Question 10

Cycles are added to a pulse, which of the following types of resolution is degraded?

Answer 10

Axial

Question 11

Increasing the PRF improves _______ resolution

Answer 11

PRF 👍😊= temporal 👍

Question 12

There is a 100% reflection on the beam strikes in interphase at _______ angle

Answer 12

Critical angle= 100% reflection

Question 13

Frequency could be detected by the human ear? ______Hz

Answer 13

2000 Hz

Question 14

Which type of image resolution is negatively affected by the placement of multiple focal zones at the area of interest?

Answer 14

Temporal

Question 15

Preferred levels of axial and lateral resolution will demonstrate/ _____ numerical value

Answer 15

Low

Question 16

60% transmission, what percent is reflected to the transducer? (Incident equation)

Incident beam (100%) equals reflected beam plus transmitted beam

Answer 16

40

Question 17

Transmit delay/receive focusing improves ______ resolution

Answer 17

LATERAL RESOLUTION hey

Question 18

Increasing line density increases

Answer 18

Spatial resolution

Question 19

Specular reflection of the greatest ________, ______, _______

Answer 19

Amplitude, intensity, frequency

Question 20

Amplitude, doubles, intensity :

Answer 20

Increases by 4!

Question 21

Impedance is defined as the _____ of particle pressure to particle velocity at a given point

Answer 21

Ratio

Question 22

What system Parimeter is defined as the ability to differentiate to separate objects on the image?

Answer 22

Resolution

Question 23

TGC necessary due to?

Answer 23

Attenuation, scatter, reflection

Question 24

If the reflector dimensions are less than the wave length of the pulse what occurs?

Answer 24

RAYLEIGH SCATTERING

Question 25

Speed of sound is primarily, depending on the______ in which the sound travels

Answer 25

SPEED= median

Question 26

How do you determine the lateral resolution for unfocused, single element transducer?

Answer 26

1/2 element diameter

Question 27

During refraction, angle of transmission increases, meaning speed ______ than before

Answer 27

Speed

Question 28

Increasing scanline density leads to improved _______ resolution

Answer 28

SPATIAL

Question 29

Reflection The greater the difference in ______ rate of the two media, the greater amount of reflection

Answer 29

Attenuation rate

Question 30

Amplitude increases by 1/2, intensity, decreases by

Answer 30

amplitude = 1/2 Intensity= 1/4

Question 31

Angle at which total reflection occurs is called the

Answer 31

Critical angle

Question 32

Diffuse reflection= occurs when the beam strikes a ______ rough surface

Answer 32

Large Rough

Question 33

Put an order from lowest to highest according to their impedance Air, blood, bones, liver

Answer 33

Lowest equals air Blood Liver Bone

Question 34

If the incident beam angle is 25°, what is the angle of reflection?

Answer 34

25

Question 35

The sonographer can improve AXIAL resolution by _____ frequency, transducer

Answer 35

Higher frequency transducer

Question 36

When the beam is absorbed by the medium, energy is lost in the form of

Answer 36

Heat

Question 37

As the sound travels through soft tissue, what happens to the period of the wave?

Answer 37

Remains constant 

Question 38

Lateral resolution is best at what location in the beam?

Answer 38

Focal zone

Question 39

As the frequency of a wave, doubles, the wave length

Answer 39

Halved

Question 40

Curved PE elements and acoustic lenses will improve which two types of resolution?

Answer 40

Elevation and lateral

Question 41

Huygen’s principle : describes the formation of the sound being by ______ sound source along the path of the beam

Answer 41

MULTIPLE

Question 42

Which of the pulse is produced from a 7MHz transducer would have the best lateral and axial resolution?

Answer 42

2mm diameter = lateral 3 pulses= axial

Question 43

M-mode = HIGHEST _______ resolution

Answer 43

M-mode= TEMPORAL

Question 44

Reflection = ________ Rhymes

Answer 44

Redirection

Question 45

Spatial pulse length= 4mm Axial resolution?

Answer 45

1/2 (4)= 2

Question 46

You are scanning the transducer that maintains a 2 scan lines per sector degree. Changes 45 to 90° sector angle. Degrades ______ resolution More scan lines = worse

Answer 46

Temporal resolution