Introduction to Acoustics (Part 1)

Week 1: Vibration & Waves

• How are time and space related? What about the relation between frequency and wavelength?
• Does the characteristic impedance of medium determine reflection and transmission?
• Do we well see the waves of a string in terms of driving point impedance?

Week 2: Acoustics Wave Equation and Its Basic Physical Measures

(1D acoustic wave equation, Acoustic Intensity and Energy, Units of Sound)

• What are the relations of acoustic pressure, density, and particle velocity?
• How do they make acoustic wave equation?
• Is acoustic wave well analogous with one dimension string wave?

Week 3: Acoustics Wave Equation and Its Basic Physical Measures

(Acoustic Intensity and Energy, Solutions of the Wave equation, Demonstration: hearing system)

• What about the relation between acoustic intensity and energy?
• How does human hearing system measure sound and its characteristics?
• Let us experience the change of sound in level and frequency!

Week 4: Waves on a Flat Surface of Discontinuity

(Normal incidence on a Flat Surface, The Mass Law)

• How mathematically express the boundary conditions at discontinuity?
• How does impedance at discontinuity determine reflection and transmission?
• When can we use mass law?

 Week 5: Waves on a Flat Surface of Discontinuity

(Transmission Loss, Snell’s Law, Transmission and Reflection of an Infinite Plate/Finite Structure)

• How different is the transmission loss of a flexible partition compared to the mass law?
• Does the obliqueness of wave play a critical role to determine transmitted and reflected wave?
• What are the roles of partition and fluid loading impedance to transmission loss?