NEXT: Crestmead

Handmade Honker

A woman with her mouth resting on a clear plastic cup. The cup as a green straw running through the length of it, with a latex glove over the cup mouth.

This honker won't help you in a traffic jam, but will be a hoot in your next jam session.

Australian Curriculum links

  • Science > Physical Sciences > Year 1 > ACSSU020
  • Science > Physical Sciences > Year 2 > ACSSU033

You'll need

  • plastic cup
  • scissors
  • drinking straw
  • latex glove
  • plasticine
  • rubber band

Try this

  1. Half way up the side of the cup, use one of the points of the scissors to make a small hole about 2 mm in diameter.
  2. Make another hole in the base of the cup, just big enough for the straw to slide through.
  3. Stretch the palm of the latex glove over the mouth of the cup and fasten it to the cup by stretching the rubber band around the rim of the cup.
  4. Slide the straw through the base of the cup until it pushes against the latex glove.
  5. Use plasticine to form a seal around the straw where it passes through the base of the cup.
  6. Play your handmade honker by blowing through the hole in the side of the cup.

What's happening?

All sounds are made by vibrations. A vibration is simply something moving backwards and forwards. When you blow through the hole on the side of the cup, the air pushes under the latex glove and escapes through the straw. As it escapes, the latex relaxes back to its original place. The sound you hear is made by the latex moving quickly backwards and forwards.

The latex vibrates and makes the sound because of pressure changes inside the cup. As you blow into the hole on the side, the pressure inside the cup builds up. This causes the latex to stretch a little, like when you blow up a balloon. As the latex stretches outwards, it uncovers the hole at the end of the straw. This allows some of the air inside the cup to rush down the straw and out into the open air. When this happens, the pressure inside the cup drops until the latex relaxes enough to cover the hole again. If you keep blowing, you can build up the pressure again, and the cycle repeats itself. This makes the latex move backwards and forwards very quickly, producing the vibrations which make the sound that you hear.

Real world links

Human ears cannot hear all sounds. For a human to hear something, the object producing the sound must vibrate between 20 and 20,000 times every second. Elephants have infrasonic hearing, which means they can hear very low pitch sounds. Some elephants can hear sounds from objects that are vibrating between 1 and 4 times a second. This means that, if you waved your hands quickly at an elephant to say hello, it could hear you waving! Dogs on the other hand have ultrasonic hearing, which means they can hear very high sounds. Some dogs can hear sounds made by objects vibrating more than 50,000 times per second!