Lesson Plan: Acoustic Impedance
This lesson plan includes the objectives, prerequisites, and exclusions of the lesson teaching students how to describe the use of reflected sound waves from boundaries of media of varying acoustic impedances to measure densities and propagation speeds.
Objectives
Students will be able to
- define the acoustic impedance of a medium as the product of the density of the medium and the speed of sound in the medium,
- relate the intensity, , of sound waves incident at a boundary between two media and the intensity, , of sound waves reflected from the boundary to the acoustic impedances of the medium the sound waves travel in before arriving at the boundary, , and the medium the sound waves travel in after being transmitted across the boundary, , applying the formula, ,
- describe the operation of piezoelectric transducers used to produce ultrasonic frequency sound waves qualitatively.
Prerequisites
Students should already be familiar with
- ,
- ,
- the inverse square law.
Exclusions
Students will not cover
- reflectometric calculations.
