Science Buddies: "Ask an Expert"

How much weight can the surface tension of water hold? And can someone walk on water? Why or why not?

There are a lot of factors that go into the answer. Warming water decreases the surface tension as does impurities. Soap is a great example of a common substance used to 'make water wetter'. If you've ever done the classic experiment where you spring ground pepper on the surface of water in a shallow pan and then put a drop of liquid soap in one corner, the pepper is pulled to the opposite end of the pan by the surface tension. It's a grade school demo but it's cool.

http://hyperphysics.phy-astr.gsu.edu/hbase/surten.html talks about surface tension in general and has a section specifically about water. Take a few minutes with a search engine and you'll find gallons of info on this.

Howard

I did a quick Google search and came up with this interesting article: http://www.livescience.com/32670-could- ... water.html

In summary, if a human were to tread water, he would either have to be moving at an insanely fast speed (almost as quick as a sprinting cheetah) or wear equipment that allows him to distribute his weight across the liquid (similar to skis on snow). However, there are animals that can walk on water, such as the basilisk lizard and water strider. Their light weight combined with their quick speed allows them to use the water's natural surface tension to their benefit.