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प्रश्न
Name two sources of sound.
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उत्तर
Each vibrating body is a source of sound. We, the human beings, produce sound when our vocal cords vibrate on blowing air through them by our lungs. Some animals like birds, frogs etc., also produce sound due to vibration of their vocal cords. But bees do not have the voice-boxes. They produce sound by moving their wings up and down very fast.
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संबंधित प्रश्न
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Fill in the blank with suitable word.
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(c) having the same composition as that on the moon?
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