Notes on sound

 

Notes on Sound

1. Definition of Sound

Sound is a form of energy that travels through a medium (such as air, water, or solids) as vibrations or waves. It is produced when an object vibrates, creating pressure waves that propagate outward.

2. Characteristics of Sound Waves

Sound waves have the following properties:

Frequency (Hz): Determines pitch (higher frequency = higher pitch).

Wavelength (m): The distance between successive crests or troughs.

Amplitude: Determines loudness (greater amplitude = louder sound).

Speed: Depends on the medium (faster in solids, slower in gases).

Period (T): The time it takes for one complete cycle of a wave.

3. Types of Sound

Audible Sound: 20 Hz – 20 kHz (heard by humans).

Infrasound: Below 20 Hz (e.g., earthquakes, elephant communication).

Ultrasound: Above 20 kHz (used in medical imaging and sonar).

4. Propagation of Sound

Sound requires a medium (air, water, or solids) and cannot travel in a vacuum.

It moves fastest in solids, slower in liquids, and slowest in gases due to particle density.

5. Reflection, Refraction, and Diffraction

Reflection: Echoes occur when sound waves bounce off surfaces.

Refraction: Sound bends when it moves between mediums of different densities.

Diffraction: Sound waves spread when passing through gaps or around obstacles.

6. Applications of Sound

Music & Communication: Speech, musical instruments, and radio transmission.

Medicine: Ultrasound imaging for diagnostics.

Industry: SONAR (Sound Navigation and Ranging) for underwater exploration.

Woul

d you like more details on a specific aspect of sound?