S2.7.1 For the adult
Sounds come from vibrations
What is happening when something makes a sound?
What this chapter teaches
Every sound is made by something that vibrates, which means it moves back and forth very fast. The movement is often too small to see, so some learners think nothing moves.
Three questions to ask
There is no one right wording. Listen for the idea.
- What do you think is moving when you hum?
- How could you show that a drum skin moves when it makes a sound?
- What do you think happens to the sound when the thing stops vibrating?
After the chapter, the learner can
- Show that a sound is made when something vibrates
- Show vibrations with rice grains on a tin or tight paper
What they copy into their notebook
A sound is made when something vibrates. To vibrate is to move back and forth very fast. A drum skin, a string and a voice box all vibrate. Rice on tight paper shows it.