Register to reply

Ultrasound - intensity reflection coefficiant calculations

Share this thread:
murdrobe
#1
Mar6-12, 11:39 AM
P: 30
1. The problem statement, all variables and given/known data

The following table gives some specific acoustic impedances
Tissue or Medium Specific acoustic impedance
Air 0.00044 x 10^6
Fat 1.38 x 10^6
Water 1.5 x 10^6
Brain 1.58 x 10^6
Blood 1.59 x 10^6
Muscle 1.6 x 10^6
Bone 6 x 10^6

this was in a table, when pasted it squashes it together, not sure how to get around that sorry.

Calculate the intensity reflection coefficient, a, for the boundary between blood and muscle



2. Relevant equations

R = Ir/Io = (Z2 – Z1)2 / (Z2 + Z1)2

R = reflection coefficient
Ir = Reflection intensity
Io = incident intensity
Z1 = acoustic impedance 1
Z2 = acoustic impedance 2


3. The attempt at a solution

Z2 – Z1 = 1.6 x 10^6 – 1.59 x 10^6 = 10,000
Z2 + Z1 = 1.6 x 10^6 + 1.59 x 10^6 = 3,190,000

10,0002 = 1x10^8
3,190,0002 = 1.01761 x 10^13

1x108 / 1.01761 x 10^13 = 9.826947455 x 10^20

R = 9.83 x 10^20

id just like someone to look over this for me please and make sure im doing this correctly as i really dont understand it and we havent been taught very well. we were kinda given the equasion and told to go away leaving me with no confidence at all. i wasnt sure whether you do the largest number - the smallest or the direction of the transition like blood/bone would be blood into bone or what....
Phys.Org News Partner Science news on Phys.org
FIXD tells car drivers via smartphone what is wrong
Team pioneers strategy for creating new materials
Team defines new biodiversity metric

Register to reply

Related Discussions
E&M reflection and refraction intensity Classical Physics 0
Ultrasound intensity in fat, muscle and bone Introductory Physics Homework 1
I want to grow plants faster using ultrasound, so how do i build an ultrasound dvice? Electrical Engineering 7
Intensity, Radius (Calculations) Introductory Physics Homework 1
Reflection intensity General Physics 3