MP Board · Class 9 · Science · SoundDifferentiate between loudness and pitch of a sound wave. On what physical factors do they depend?

Loudness and pitch are two fundamental characteristics of sound that depend on different wave properties:

1. Loudness:

• Loudness refers to the degree of sensation produced by a sound wave on human ears, determining whether a sound is loud or soft.
• It depends primarily on the amplitude of the vibrating object producing the sound.
• Amplitude represents the maximum displacement of particles from their mean position. A larger amplitude carries more energy, producing a louder sound.
• Loudness is measured in decibels (dB).

2. Pitch:

• Pitch is the subjective characteristic of sound that allows us to distinguish between a shrill (high-pitched) sound and a flat/grave (low-pitched) sound.
• It depends directly on the frequency of the sound wave.
• Frequency represents the number of vibrations or wave cycles completed per second. Higher frequency corresponds to a higher pitch (e.g., a whistle or female voice), while lower frequency corresponds to a lower pitch (e.g., a drum or male voice). \nIn summary, loudness is determined by amplitude, whereas pitch is determined by frequency.