Range Of Hearing

Key Notes:

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🔊 What is Range of Hearing?

• The range of hearing is the range of sound frequencies that the human ear can hear.

👨‍👩‍👧 Human Range of Hearing

• Humans can hear sounds from 20 Hz to 20,000 Hz (20 kHz).
• Sounds below 20 Hz are called infrasonic sounds.
• Sounds above 20,000 Hz are called ultrasonic sounds.

🐘 Infrasonic Sounds (Below 20 Hz)

• Not audible to humans.
• Elephants and whales use infrasonic sounds for long-distance communication.
• These sounds can travel long distances through air and water.

🦇 Ultrasonic Sounds (Above 20,000 Hz)

• Not audible to humans.
• Bats and dolphins use ultrasonic sounds for echolocation.
• Used in medical imaging (ultrasound) and SONAR.

🧠 Factors Affecting Hearing

• Age: Hearing range reduces with age (especially high-frequency sounds).
• Loud noise exposure can damage hearing.
• Health of the ear also affects hearing ability.

🔔 Audible vs Loudness

• Frequency (Hz) determines pitch (high or low sound).
• Amplitude determines loudness, not the hearing range.

📌 Key Terms to Remember

• Audible sound: 20 Hz – 20,000 Hz
• Infrasonic sound: Below 20 Hz
• Ultrasonic sound: Above 20,000 Hz
• Hz (Hertz): Unit of frequency