Chapter 16 - Section 16.4 - Study Guide - Assess Your Learning Outcomes - Page 625: 1

Sound is generated by the vibration of objects or substances in the surrounding environment. When an object vibrates, it creates pressure variations in the air or a medium, which travel as sound waves. These waves consist of compressions (regions of higher pressure) and rarefactions (regions of lower pressure) that propagate through the air or another medium. **Physical Properties of Sound Waves:** 1. **Frequency (Measured in Hertz - Hz):** Frequency refers to the number of cycles or vibrations a sound wave completes in a given unit of time. It is measured in Hertz (Hz), where 1 Hz represents one cycle per second. The frequency of a sound wave determines its pitch. Higher-frequency waves are perceived as higher-pitched sounds, while lower-frequency waves are perceived as lower-pitched sounds. 2. **Amplitude (Measured in Decibels - dB):** Amplitude represents the magnitude of the pressure variations in a sound wave. It is a measure of the wave's intensity or energy and is measured in decibels (dB). The amplitude of a sound wave determines its loudness. Greater amplitude corresponds to louder sounds, while smaller amplitude corresponds to quieter sounds. **Sensory Qualities of Sound:** 1. **Pitch:** Pitch is the perceptual quality of sound that corresponds to the frequency of a sound wave. Higher-frequency waves are perceived as higher-pitched sounds, such as a bird's chirp, while lower-frequency waves are perceived as lower-pitched sounds, like a deep bass note in music. 2. **Loudness:** Loudness is the perceptual quality of sound that corresponds to the amplitude of a sound wave. Greater amplitude results in a louder perception of sound, like the volume of music played at a high setting, while smaller amplitude leads to a quieter perception, like a whisper. It's important to note that the human auditory system is sensitive to a wide range of frequencies and amplitudes. The audible range of frequencies for most humans is approximately 20 Hz to 20,000 Hz, while the range of amplitudes that can be perceived without discomfort spans a vast range from the faintest sounds to the threshold of pain. In summary, sound is generated by the vibration of objects, and its physical properties of frequency (measured in Hz) and amplitude (measured in dB) correspond to the sensory qualities of pitch and loudness, respectively. These properties contribute to the diverse range of sounds we hear and how we perceive them in terms of pitch and volume.

Sound is generated by the vibration of objects or substances in the surrounding environment. When an object vibrates, it creates pressure variations in the air or a medium, which travel as sound waves. These waves consist of compressions (regions of higher pressure) and rarefactions (regions of lower pressure) that propagate through the air or another medium. **Physical Properties of Sound Waves:** 1. **Frequency (Measured in Hertz - Hz):** Frequency refers to the number of cycles or vibrations a sound wave completes in a given unit of time. It is measured in Hertz (Hz), where 1 Hz represents one cycle per second. The frequency of a sound wave determines its pitch. Higher-frequency waves are perceived as higher-pitched sounds, while lower-frequency waves are perceived as lower-pitched sounds. 2. **Amplitude (Measured in Decibels - dB):** Amplitude represents the magnitude of the pressure variations in a sound wave. It is a measure of the wave's intensity or energy and is measured in decibels (dB). The amplitude of a sound wave determines its loudness. Greater amplitude corresponds to louder sounds, while smaller amplitude corresponds to quieter sounds. **Sensory Qualities of Sound:** 1. **Pitch:** Pitch is the perceptual quality of sound that corresponds to the frequency of a sound wave. Higher-frequency waves are perceived as higher-pitched sounds, such as a bird's chirp, while lower-frequency waves are perceived as lower-pitched sounds, like a deep bass note in music. 2. **Loudness:** Loudness is the perceptual quality of sound that corresponds to the amplitude of a sound wave. Greater amplitude results in a louder perception of sound, like the volume of music played at a high setting, while smaller amplitude leads to a quieter perception, like a whisper. It's important to note that the human auditory system is sensitive to a wide range of frequencies and amplitudes. The audible range of frequencies for most humans is approximately 20 Hz to 20,000 Hz, while the range of amplitudes that can be perceived without discomfort spans a vast range from the faintest sounds to the threshold of pain. In summary, sound is generated by the vibration of objects, and its physical properties of frequency (measured in Hz) and amplitude (measured in dB) correspond to the sensory qualities of pitch and loudness, respectively. These properties contribute to the diverse range of sounds we hear and how we perceive them in terms of pitch and volume.