Pitch, Loudness & Quality of Sound Waves

Understanding Sound Waves

Sound waves are vibrations that travel through a medium, like air or water, and can be heard when they reach a person's or animal's ear. Let's explore the characteristics of sound waves: pitch, loudness, and quality.

Pitch

• Definition: Pitch refers to how high or low a sound is perceived. It is determined by the frequency of the sound wave.
• Frequency: Higher frequency means higher pitch, and lower frequency means lower pitch.
• Unit: Frequency is measured in Hertz (Hz).

Loudness

• Definition: Loudness is the perception of the intensity of a sound. It depends on the amplitude of the sound wave.
• Amplitude: Larger amplitude means louder sound, and smaller amplitude means softer sound.
• Unit: Loudness is often measured in decibels (dB).

Quality (Timbre)

• Definition: Quality, or timbre, is what makes two sounds with the same pitch and loudness sound different.
• Overtones: The presence of overtones (additional frequencies) affects the quality of the sound.
• Example: A piano and a violin playing the same note sound different due to their unique overtones.

Resonance and Musical Instruments

Resonance occurs when an object vibrates at its natural frequency due to an external force. This principle is used in musical instruments to amplify sound.

• Resonance Boxes: Used in instruments like guitars and violins to enhance sound quality by amplifying vibrations.
• Sonometer: A device used to study the relationship between frequency, tension, and length of a vibrating string.