Thursday, October 31, 2013

Halloween Experiment: Haunted, Screaming Cup!

If you think haunted houses are scary, you're definitely going to want to make haunted drinkware tonight! If you'd rather scare than be scared, invite some friends over and get them spooked by making the cup scream where they can't see it!

Here's what you'll need:
  • A plastic drinking cup
  • Yarn or cotton string (nylon string won't work as well)
  • 1 paper clip
  • 1 paper towel
  • 1 nail
  • Scissors 
  • Water
Not let's get started!
  1. Cut a piece of yarn that measures about 20 inches.
  2. Carefully punch a hole in the center of the bottom of the cup with the nail.
  3. Tie one end of the yarn to the middle of the paper clip.
  4. Push the other end of the yarn through the hole you punched in the bottom of the cup and pull it through.
  5. Get a piece of paper towel about the size of a dollar bill. Fold it once and get it damp in the water.
  6. Now it's time to make the cup scream! Hold the cup firmly in one hand and wrap the damp paper towel around the string near the cup. While you squeeze the string, pull down in one continuous motion so that the paper towel tightly slides along the string.
What about the science? This is how a sounding board works. The vibrations from the string would practically be mute without the cup, but when you add the cup, it spreads the vibrations and amplifies them.

Check out Science Bob's video of this experiment. Here, he pulls the string in short jerks to make it sound like a chicken.