Sound is a fascinating form of energy. As you sit there reading this, there is energy flowing all around you in the form of light waves, sound waves, radio waves, heat and more. You are constantly being bombarded by energy. Energy is everywhere, all the time.Moving by waves at amazing speeds, sound energy brings you knowledge about the world around you. Does a tree make a sound if it falls without anyone there to hear it? This section will answer that question and many others. You can get started by watching this video, and afterward either read more about it or start your experiments!
Energy moves in waves. Before we get in over our heads talking about sound waves, though, we need to spend some time on this vibration thing. This lesson we will be taking a careful look at vibration and frequency.

Scientific Concepts:

  • Energy moves by waves.
  • All waves begin as vibrating particles
  • The particles vibrate back and forth. They do not move along the wave.
  • Frequency is the amount of vibrations there are in a given amount of time.
  • Hertz is a measurement of frequency and is one vibration per second.
  • Waves are the way energy moves from place to place. Waves are energy-mobiles.
  • Particles in a wave are moving a distance against a force. They are having work done on them and they can do work.
  • A transverse wave is a wave where the particle moves perpendicular to the medium.
  • A longitudinal wave is where the particle moves parallel to the medium.
  • Amplitude is the height of the wave.
  • Energy is all around us all the time.
  • Antennae are necessary to pick up energy.
  • Our bodies have three antennae; eyes, ears, and skin.
  • Eyes can detect light waves, which are a small portion of the electromagnetic spectrum.
  • Skin can detect heat, which is another even smaller portion of the electromagnetic spectrum.
  • Ears can detect sound waves.
  • Our antennae pick up the energy, sound waves, heat, or light. Our brain interprets them.
  • Since we have two ears we are very good at determining the direction of a sound.
  • Our ears are also very good at telling the difference between sound frequencies.
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Special Science Teleclass: Sonic Vibrations
This is a recording of a recent live teleclass I did with thousands of kids from all over the world. I’ve included it here so you can participate and learn, too! Sound is a form of energy, and is caused by something vibrating. So what is moving to make sound energy? Molecules. Molecules are vibrating …

Continue reading "Special Science Teleclass: Sonic Vibrations"

What is Frequency?
In this experiment you will be adjusting the length of string of a pendulum until you get a pendulum that has a frequency of .5 Hz, 1 Hz and 2 Hz. Remember, a Hz is one vibration (or in this case swing) per second. So .5 Hz would be half a swing per second (swing one way but not back to the start). 1 Hz would be one full swing per second.
Ear Tricks
Think of your ears as 'sound antennas'.  There's a reason you have TWO of these - and that's what this experiment is all about.  You can use any noise maker (an electronic timer with a high pitched beep works very well), a partner, a blindfold (not necessary but more fun if you have one handy), and earplugs (or use your fingers to close the little flap over your ear - don't stick your fingers IN your ears!).
Transverse and Longitudinal Waves
Since we can't see soundwaves as they move through the air, we're going to simulate one with rope and a friend. This will let you see how a vibration can create a wave. You'll need at least 10 feet of rope (if you have 25 or 50 feet it’s more fun), a piece of tape (colored if you have it), a slinky, and a partner. Are you ready?
How a Record Player Works
Before CDs, there were these big black discs called records. Spinning between 33 and 45 times per minute on a turntable, people used to listened to music just like this for nearly a century. Edison, who had trouble hearing
BONUS! Nine Sonic Vibes Experiments to Mystify Your Kids
Cut a piece of tissue paper the same length as a plastic comb (make sure the comb's teeth are close together). Fold the tissue paper in half, wrapping it around the teeth of the comb.  Place it lightly between your lips and hummm... you'll feel an odd vibrational effect on your lips as your kazoo makes a sound!