An ultrasound pulse reaches a boundary inside the body. Some of the pulse is reflected and some is transmitted.
Why is this useful when forming an image of several tissues?
One echo locates this boundary; reflected waves continue towards deeper boundaries.
One echo locates this boundary; transmitted waves can reach deeper boundaries.
Transmitted waves locate this boundary; absorbed waves return from deeper boundaries.
Absorbed waves locate this boundary; reflected waves pass through deeper boundaries.
112 exam-style questions on Edexcel GCSE Physics 4.3 Sound, ultrasound and infrasound, covering 4.3.1 Sound waves, vibrations and the human ear, 4.3.2 Ultrasound and infrasound, 4.3.3 Uses of ultrasound and infrasound, and 4.3.4 Sound waves passing between media. Each one has a worked solution and a mark scheme showing where the marks go.