Determine the fraction of the intensity of an ultrasound beam that is reflected when a beam is incident normally on a boundary between water and fat. (Use values from Table ) Material Density / kg m - 3 Speed of sound / ms - 1 Acoustic impedane / 10 6 kgm - 2 s - 1 Lead zirconate titanate 7650 3790 29 . 0 Quartz 2650 5700 15 . 1 Polyvinylidese diflouride 1780 2360 4 . 20

Fraction of intensity is given by I r I o = ( Z 2 - Z 1 ) 2 ( Z 2 + Z 1 ) 2 = ( 1 . 34 - 1 . 50 ) 2 ( 1 . 34 + 1 . 50 ) 2 = 3 . 2 × 10 - 3

E M B I B E

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 30 - Medical Imaging>Questions

David Sang and Graham Jones Solutions for Chapter: Medical Imaging, Exercise 7: Questions

Author:David Sang & Graham Jones

David Sang Physics Solutions for Exercise - David Sang and Graham Jones Solutions for Chapter: Medical Imaging, Exercise 7: Questions

Attempt the free practice questions on Chapter 30: Medical Imaging, Exercise 7: Questions with hints and solutions to strengthen your understanding. Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access solutions are prepared by Experienced Embibe Experts.

Questions from David Sang and Graham Jones Solutions for Chapter: Medical Imaging, Exercise 7: Questions with Hints & Solutions

HARD

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 30 - Medical Imaging>Questions>Q 12

Calculate the acoustic impedance of muscle tissue. (Density $= 1075 kg m^{- 3};$ speed of sound $= 1590 m s^{- 1}$ .)

HARD

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 30 - Medical Imaging>Questions>Q 13

Determine the fraction of the intensity of an ultrasound beam that is reflected when a beam is incident normally on a boundary between water and fat. (Use values from Table )

Material	$Density / {kg m}^{- 3}$	$Speed of sound / {ms}^{- 1}$	$Acoustic impedane / 10^{6} {kgm}^{- 2} s^{- 1}$
Lead zirconate titanate	$7650$	$3790$	$29.0$
Quartz	$2650$	$5700$	$15.1$
Polyvinylidese diflouride	$1780$	$2360$	$4.20$

HARD

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 30 - Medical Imaging>Questions>Q 14

The ultrasound image shown in Figure clearly shows the baby's skin and some bones. Explain why these show up clearly while softer organs inside its body do not.

Question Image