Sound

1. without sound, there won't be music :>

2. Characteristics of Sound (Reg 1-5)

2.1. New node

3. Applications of Sound (Reg 6-10)

4. What is Sound? (Reg 11-15)

4.1. New node

4.1.1. New node

5. Production of Sound (Reg 16-20)

5.1. New node

5.2. New node

5.3. New node

6. Transmission of Sound (Reg 21-25)

6.1. Reflection

6.2. New node

7. Detection of Sound (Reg 26-30)

7.1. Function of Ear

7.2. New node

8. Speed of Sound (Reg 31-33)

9. Loudness and Pitch (Reg 11-15)

10. music!

11. testing

12. dsgdgdf

13. sfsgskjsgklfs