Sound

Medium of Communication

• Sounds help us communicate with each other
• Different types of sounds: Automobiles, Music, Chopping sounds, etc.

Sources of Sound Production

• Sound can be natural or man-made
• How humans produce sound
• Musical Instruments: Harmonium, Tabla, Sitar, Vocal cords

How Sound is Produced

• Sound is produced by vibrations
• Example: Striking a tabla, hitting a metal stick with a wooden stick

Study of Sound

• Vibrating bodies produce sound
• Example: Observing vibrations in a metal cup filled with water

Musical Instruments

• Manjira, Jal Tarang, and other instruments
• Vibrations produce sound

Human Body and Sound

• Sound is produced by the vibrations of vocal cords
• Location of vocal cords and how they function

Propagation of Sound

• Sound propagates through mediums (Air, Water, Solid)
• Sound does not propagate in a vacuum

Characteristics of Sound

• Loudness: Depends on amplitude
• Pitch: Depends on frequency
• Audible Range: 20 Hz - 20,000 Hz

Noise Pollution

• Unwanted sounds are called noise
• Health effects of noise pollution

Control Measures

• Greenery plantation, controlled volume levels
• Keeping industries away from residential areas

Structure of the Human Ear

• Sound waves travel through the ear canal to the eardrum
• Eardrums vibrate, and the brain interprets the vibrations