Flashcards in Lesson 8 (Part 2) Deck (13)
What does delta z mean when it is equal to 0?
- no echoes
The reflection and scattering of sound waves
What are 2 types of incidences?
Denotes a direction of travel of the ultrasound wave perpendicular to the boundary between 2 medias
Does transmitted sound change direction?
No, it continues to the second medium
What does intensities depend on?
Incident intensity at the boundary and the impedance of the media on either side of the boundary
What happens to impedance if density and propagation speed increases?
What happens to the IRC if the difference of impedances increase?
What does transmission coefficient depend on?
The reflection coefficient
What happens to the ITC if the IRC increases?
What happens when ultrasound encounters a boundary with perpendicular incidence?
The impedances of the tissue must be different to produce a reflection
What 2 things must be known in order to calculate the reflected intensity?
1. 2 media impedances
2. Incident intensity