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Unit 6: Sound Page 18
What is moving to make sound the right frequency and enough
energy? energy, your ear drum antennas
will pick it up and your brain will
Molecules. Molecules are vibrating turn the energy into what we call
back and forth at fairly high rates sound.
of speed, creating waves. Energy
moves from place to place by Sound is caused by something
waves. Sound energy moves by vibrating. If you can hear it, you
longitudinal waves (the waves that can bet that somewhere,
are like a slinky). The molecules something is vibrating molecules
vibrate back and forth, crashing and those molecules are vibrating
into the molecules next to them, your ear drums. The sound may be
causing them to vibrate, and so on coming from a car, thunder, a
and so forth. All sounds come from balloon popping, clapping hands, or
vibrations. your gold fish blowing bubbles in
her tank. However, no matter
Do you remember when we where it’s coming from, what you
talked about frequency and are hearing is vibrating particles,
Hertz? Those are both terms to usually vibrating air molecules.
describe vibrations, right?
Frequency describes how fast Natural Frequency
something is vibrating. Hertz is a
measurement of frequency and one Everything is vibrating.
Hertz is one vibration per second. Absolutely everything is wiggling
and jiggling, and most of those
Our ears are our sound things are doing it really fast! Now,
antennas. When something I can hear you saying
vibrates it causes energy to move “Hey...maybe you need to check
by longitudinal waves, from the your eyesight or lay off the coffee
object vibrating to our ears. If that because in my house, I’m not
something is vibrating between seeing everything jiggling.”
about 60 Hz and 20,000 Hz it will
cause your ear drum to vibrate. Well, you may be right about
This is sound. both of those things, but
indeed, everything is wiggling
When something vibrates, it and jiggling. I don’t mean that
pushes particles. These pushed your couch is jumping up and down
particles create a longitudinal or that your dinner table is
wave. If the longitudinal wave has vibrating out of the room or
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