Echoes and reflections

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3. TRY this:

Q1: Which kind of surface soaks up sound. How would we test for this?

[Answer]

When a sound reaches a hard surface it will bounce off it. If the sound gets bounced back to us, we hear this as a delayed sound. We call it an echo.

If the surface is soft much of the vibration is soaked up by the soft surface and we get, at most, a soft, muffled sound.

We can use these ideas to affect sounds in rooms where we live as well as in concert halls.