Duck Call Device
Materials:
- One plastic straw from your kitchen or local fast food restaurant
- Scissors
- Lungs (don't worry you already have them)
1. Use your fingers to press on one end of the straw to flatten it - the flatter
the better.
2. Cut the flattened end of the straw into a point (see below).
3. Flatten it out again real good.
4. Now take a deep breath, put the pointed end of the straw in your mouth
and blow hard into the straw. If all goes well you should hear a somewhat
silly sound coming from the straw. The smaller you are, the harder it may be
to get a good sound - sometimes adults can get more of a sound thanks to
their bigger lungs. If you still have trouble, try flattening it out some more or
cutting the straw in half.
5. Don't stop there - try cutting the straw different sizes to see how the sound
changes, or make another identical straw and add the pointed end of the
new straw to the uncut end of the first straw (to make the first straw longer)
The sound will be very different, (more like a moose call!) and you will have
to blow even harder, but give it a try.
How it Works:
All sounds come from vibrations. That little triangle that you cut in the straw
forced the two pieces of the point to VIBRATE very fast against each other
when you blew through the straw. Those vibrations from your breath going
through the straw created that strange duck-like sound that you heard. Now
you will never be bored again when you go to a fast food restaurant! Have fun!
The project above is a DEMONSTRATION. To make it a true experiment, you
can try to answer these questions:
1. Which size straw call sound the most like a duck?
2. Which length of straw is the easiest to get a sound? Which is the hardest?
3. Does the diameter of the straw affect the sound it produces?
Credits Sciencebob.com
 | |  | |  | |  | |  | |  |