Sound is a kind of energy, Sound is all around us, IIt is produced when objects move back and forth. This back-and-forth movement is called vibration., A strong vibration makes more air vibrate and produces a louder sound., Sounds may be pleasant and unpleasant, Pleasant sound, it makes you feel good when you hear it., A very loud and annoying sound is called noise. It is a form of pollution and can be harmfull and can damage your ears., Loss of hearing - Loud sounds can damage the sensitive parts of the ear which will lead to loss of hearing, Disturbance during work activities - One cannot concentrate on doing activities if there is a lound sound, Restlessness - Too much exposure to loud sounds can make a person restless and increase his or her level of stress, DId you know that dogs can hear sounds or noises that human cannot.,

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