Physics for IGCSE & O level - Waves And Sounds (Section 1 - No. 19)
In the context of medical ultrasound, what does the use of an echo-sounder rely upon?
Reflection of the ultrasound waves
Absorption of the ultrasound waves
Refraction of the ultrasound waves
Dispersion of the ultrasound waves
Explication
An echo-sounder relies on the reflection of ultrasound waves.