In Class 8, students learn about sound as a part of their science curriculum. Sound is a form of energy that comes from vibrations. These vibrations create sound waves, which can move through mediums such as air, water, or solids. Some key points about sound include:
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Vibration: Sound is produced by vibrating objects. Vibration is the to-and-fro or back-and-forth movement of an object.
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Medium: Sound needs a medium to travel and cannot travel in a vacuum. It can travel through air, water, and solids.
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Loudness and Pitch: The volume or loudness of a sound depends on its amplitude, which is the force with which an object vibrates. The pitch of a sound is determined by its frequency, which is the number of oscillations per unit time. The audible range of sound for humans is 20 Hz to 20 kHz, known as the Sonic range.
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Audible and Inaudible Sounds: Sounds below 20 Hz are inaudible and are called infrasonic, while sounds above 20 kHz are also inaudible and are called ultrasonic.
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Applications of Sound: Sound plays an important role in our daily lives. We use sound to communicate, perceive our surroundings, and for various other purposes.
