Sound

1. Musical Sounds and Noise

1.1. Musical Instruments

1.1.1. String Instruments

1.1.2. Percussion Instruments

1.1.3. Wind Instruments

2. How Sound Travels

2.1. Speed of Sound

2.2. Reflection and Absorption

2.2.1. Echo

2.2.2. Sound Absorption

3. Producing and Hearing Sound

3.1. Sound Produced

3.2. Hearing Sound

3.2.1. Ear Structure

3.2.1.1. Outer Ear

3.2.1.2. Middle Ear

3.2.1.3. Inner Ear

3.2.2. Audible and Inaudible Sound

4. Characteristics of Vibrations

4.1. Amplitude

4.2. Frequency

4.3. Time Period

5. Characteristics of Sound

5.1. Loudness

5.1.1. Amplitude of Vibration

5.1.2. Area of Vibrating Body

5.1.3. Distance of Listener from source of sound

5.2. Pitch

5.2.1. Low

5.2.2. High

5.3. Quality

6. Noise Pollution

6.1. Hazards of Noise Pollution

6.2. Reducing Noise Pollution