lesson
Sound begins with a vibration
1 · Learn
A vibration is a repeated back-and-forth movement. A plucked string vibrates and makes the surrounding air vibrate. Those vibrations can reach our ears as sound.
The vibrating object may move too little or too quickly for us to see clearly. Not seeing movement does not prove that no vibration is happening.
2 · Worked example
A ruler held firmly on a desk can vibrate at its free end when an adult demonstrates it gently. I connect the visible movement with the sound.
3 · Your turn
What does a plucked string do that produces sound?
Check your answer
It vibrates, causing vibrations in the surrounding material such as air.
4 · Apply your learning
Observe an adult's gentle safe instrument demonstration and describe the source that vibrates.
Adult guidance and safety
Keep sound comfortable. No snapping bands near faces, placing objects in ears or loud sounds next to anyone's ear.
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With an adult, look at a safe real example or a checked photograph. Name the example and say which you used. Record what you actually notice. Do not taste plants or materials, approach unknown animals or invent missing observations.
Ask your teacher for support with the method and recording. A prediction is what you think might happen; an observation is what you actually see, hear or feel safely.
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