Water Falling Sideways

Wednesday, December 16th, 2009

Normally when you spill water out of a jug, it will fall straight down. It is gravity that pulls it down. We could get water to spill sideways. First of all we tried lots of things - pouring it out of the side or the back of the jug, using our fingers or hands to get the water to spill sideways. We managed best of all when we used a piece of string, and got the water to run sideways along the string.

Water sticks to string with surface tension. Surface tension is like a skin of water caused by water molecules holding tightly on to one another. They were holding so tightly to each other around the string, that even when the string is held sideways, the water will hold on to it and drip sideways, instead of straight down.