Tuesday, May 25, 2010

Blog Swap with Melanie from Experimental Mum.

This is so exciting!  Melanie has a ton of really cool ideas for science experiments on her blog Experimental Mum.  So when you are done reading here then hop on over the pond and check out her other posts!

I'm Melanie Riddell, I live in the Highlands of Scotland with my husband Stuart and our two daughters. I love being a work from home Mum running my science education business, Sizzling Science from my wee office caravan.

tennisIf your household has gone Wimbledon daft, here's an tennis experiment to add to the mix!



What You Need:

  • Freezer
  • Two identical tennis balls
  • Plastic bag
  • Video Camera (optional)

What To Do:

  1. Place one of the rubber balls into a plastic bag and place the bag into the freezer. Keep the other ball in a warm place like your pocket.
  2. After a few hours, bounce both balls at the same time and compare their bounce. If you have a video camera handy you could ask someone to record you bouncing as this will make it easier for you to see.
  3. You should find that the warm ball bounces slightly higher. The cold ball should bounce about 80% as high.

What's Going On:



The materials in the balls are made up of long stretchy polymers. Normally when you drop the ball its molecules are stretched when it hits the floor and the ball is slightly deformed. After a moment, the molecules return to their original position causing the ball to bounce upwards. When the ball is frozen the polymers are less pliable and this makes the ball less bouncy.



Photo Credit: DaDaAce


1 comment:

Rebecca (me!) said...

Sounds like something my boys would love! Thanks!

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