USE A STRAW TO STAB A POTATO

WE NEED:

• Plastic drinking straws.
• A raw potato.

HOW TO DO IT:

1. Take the plastic drinking straw.
2. Try quickly stabbing the potato.
3. Repeat the experiment with a new straw.
4. Put your finger over the top, covering the hole.
5. Try quickly stabbing the potato.    

    

PREDICTIONS:

The straw is going to stab the potato in both tries.


RESULTS:

Placing your thumb over the hole at the top of the straw improves your ability to pierce the potato skin and push the straw deep into the potato. The first time you tried the experiment you may have only pierced the potato a small amount, so why are you more successful on the second attempt?

Covering the top of the straw with your thumb traps the air inside, forcing it to compress and helping the straw not being deformed as you stab the straw through the potato skin. This makes the straw strong enough to pierce the potato, unlike the first attempt where the air is pushed out of the straw.

STRAW

+

THUMB (AIR TRAPPED - COMPRESSED)

=

PIERCED POTATO

MY OPINION: 

This experiment has been great because I did not expect the straw is nailed to the potato.

BY: ALBA