Why Why Why Kids

How Things Work 3-minute video · ages 4-8 · free coloring page

How does a piano work?

When you press a piano key, a beautiful sound comes out. But how does a piano work?

Hammy peeking over the video
3 min
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The answer in three parts

Why?

  1. Every key is really a long see-saw.

    When your finger pushes one end down, the other end pops up, and it tosses a hammer toward the strings.

  2. Bonk! The hammer hits a string, and the string wiggles.

    The hammer bounces right back, as quick as a blink. The string wiggles back and forth, hundreds of times every second. This is called vibration. The wiggle pushes the air, and the air carries it to your ears. That is sound!

  3. The soundboard makes it loud.

    One thin string is very quiet. So the strings rest on a big, thin sheet of wood called the soundboard. The whole board wiggles too, and pushes lots and lots of air. Now the sound can fill the room.

For grown-ups: Each hammer's head is covered in soft felt, so the sound is warm and not clanky. A note stops when you let go of the key: a soft pad called a damper hugs the string and the wiggling stops. Step on the right pedal and all the dampers lift up together, so the notes keep ringing even after you let go.

Inside a piano

  • Stringsmore than two hundred
  • Hammerseighty-eight
  • Soundboarda big
  • Damperssoft pads that stop the notes
  • Pedalsdown by your feet

A tiny experiment

Try it!

Make a box hum

You need: an empty box and a rubber band

  1. Stretch a rubber band around an empty box.
  2. Pluck it. See it wiggle? Hear it hum?
  3. Now pull it tighter. Does the note go higher?

What happened? The wiggling band pushes the air, just like a piano string. Pull it tighter, and the note goes higher!

Did you know?

Press a key gently, and the hammer taps softly. Press it hard, and the hammer hits hard. Loud! That is how the piano got its name. Its full name, pianoforte, means soft and loud.

Long, thick strings wiggle slowly and make low, deep notes, like a bear. Short, thin strings wiggle fast and make high, tiny notes, like a little bird.

Hammy the piano hammer

Your guide in this video

I'm Hammy, a little hammer who lives inside a piano. Let's solve a very musical mystery!

Hammy is one of the eighty-eight little hammers inside a piano. Hammy's head is covered in soft, fuzzy felt.

Meet all the characters

For grown-ups

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