Sound

Sound

1. Pitch

   • The more the cycle of vibration (frequency), the higher the pitch.
   • Human audible range range from 20 Hz to 20,000 Hz.

2. Speed of sound

   • Air: 330 m / s
   • liquid: 1500 m / s
   • Solid: 5000-6000 m / s

3. How we hear sound?

   • The ear canal transmit the sound to the eardrum which it will vibrate and send them as electrical signals to the brain.

4. Loudness

   • Greater vibrations with greater energy produce louder sounds.

5. Uses of sound

   • Warning of danger
     • Loud sirens warn people of approaching danger or alert people to an emergency vehicle.
   • Entertainment
     • Sounds that are pleasant to our ears
   • Communication
     • We talk to each other to communicate.

6. Sonar

   • Speed of sound x Time taken

7. Ultrasound: above 20,000 Hz

   • Intrasound: below 20 Hz

Images and files in the map