Vibrations & sound
Understand that vibrating materials can make sound, and that sound can make materials vibrate
What a learner can do afterwards
- Describe that sounds are made when objects vibrate (move back and forth quickly)
- Give at least three examples of vibrating objects making sound (drum skin, guitar string, voice box)
- Describe an observation showing that sound can make another object vibrate without touching it.
1 · Read
A vibration is a back-and-forth movement. Vibrating objects can make sound by pushing on nearby air. Sound travels through air to your ears and makes your eardrums vibrate. Some vibrations are too slow or too quiet for you to hear.
Plucking a guitar string starts it moving back and forth. It vibrates and makes sound. Its movement may look blurry or be too small to see. A closed book and a resting rock are not sound-making examples.
The folds inside your voice box vibrate when you sing. Touch the outside of your throat gently to feel the buzz. The buzz comes from vibration, not from your throat cooling or growing.
An adult puts rice on a tight, thin bowl cover. A nearby speaker plays at a comfortable volume without touching the bowl. If sound makes the cover vibrate enough, the rice moves. Rice may stay still in some setups. Do not touch a speaker's moving cone.
A tap can move a bowl cover and the rice on it. If the speaker is off and someone taps the cover, the tap explains the movement. Movement alone does not prove that sound from a speaker caused it.
Vibrating objects can make sound. Sound can make other objects vibrate, including your eardrum.
These reading passages were written for this learning dataset. The flashcards describe sound and vibration facts.
2 · Watch
Take it off screen
Where it sits
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.