Acoustic impedance
What Acoustic impedance means in Physics A-Level, as defined for AQA, OCR.
Definitions of Acoustic impedance
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Reference: AQA
Echoes return from boundaries where this changes between tissues, and its difference between two media determines the amplitude of the returning echo.
A property of a medium that describes how much resistance it offers to the passage of ultrasound, defined as Z = ρc.
Defined as Z = ρc, the product of tissue density and the speed of sound in that tissue.
Topics that use Acoustic impedance
- Ultrasound imaging (A-level only) (AQA A-Level)
- Using ultrasound (OCR A-Level)
Related terms
- A-scan
- B-scan
- Coupling gel
- Intensity reflection coefficient
- Piezoelectric effect
- Acoustic impedance and reflection
- Acoustic impedance mismatch
- Acoustic matching
Using Acoustic impedance in the exam
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