How Microphones Catch Your Voice
Have you ever sung into a microphone and heard your voice come out of a big speaker, loud and huge? A tiny whisper can fill a whole room! How does a little microphone do that? A microphone has a special job: it catches sound and turns it into a signal that machines can use. Let's find out how it works.
What You'll Learn
In this lesson you will: - Learn that sound is made of tiny wiggles in the air - Find out about the wiggly part inside a microphone - See how a microphone turns your voice into a signal - Try making your own pretend microphone
Sound Is a Wiggle
When you talk or sing, the air in front of your mouth wiggles back and forth very fast. These wiggles are called sound waves. You cannot see them, but you can feel them! Put your hand on your throat and hum a low sound. Do you feel it buzzing? That buzz is making the air wiggle, and that wiggle is your voice traveling out.
Stretch a rubber band and pluck it. See it shake back and forth? That shaking makes the air wiggle, and that is exactly how sound is made.
The Wiggly Part Inside
Inside a microphone is a thin, floppy part called a diaphragm (say it: DYE-uh-fram). It is a bit like a tiny drum skin. When the wiggles from your voice hit the diaphragm, it wiggles too - in and out, in and out. The louder you sing, the bigger it wiggles!
From Wiggle to Signal
Here is the clever part. As the diaphragm wiggles, the microphone changes those wiggles into a tiny electric signal. A signal is like a secret message the wires can carry. That signal zooms down the wire to a speaker, which makes the air wiggle again - but much bigger. That is why your quiet voice comes out big and loud!
Match each part to what it does.
Terms
Definitions
Drag terms onto their definitions, or click a term then click a definition to match.
What is sound made of?
What does the diaphragm inside a microphone do?
Make a cup-and-string phone
With a grown-up's help, poke a small hole in the bottom of two paper cups. Push one end of a long string through each hole and tie a knot inside. Pull the string tight with a friend, then talk into your cup while your friend listens with theirs. Deliverable: try it and share one sentence about what you heard - your voice made the cup bottom wiggle, just like a diaphragm!
Flashcards — click each card to reveal the answer
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