How Trees Bend the Laws of Physics

Hope this was worth the wait! So many people helped with this video: Prof John Sperry, Hank Green, Henry Reich, CGP Grey, Prof Poliakoff, my mum filmed for me in beautiful Stanley Park and Jen S helped with the fourth version of the script. Prof John Sperry http://biologylabs.utah.edu/sperry/john.html Hank Green (SciShow) http://www.youtube.com/user/scishow Henry Reich (minutephysics) http://www.youtube.com/user/minutephysics CGP Grey http://www.youtube.com/user/cgpgrey Prof Poliakoff (Periodic Videos) http://www.youtube.com/user/periodicvideos Also thanks to the Palais de la Decouverte - they helped me with the whole vacuum pump setup in Paris. No, I could not actually suck water up 10m - I did about 4m, but the vacuum pump was easily able to do it and I saw spontaneous boiling on all of our various trials. Footage from this may end up on 2Veritasium. Trees create immense negative pressures of 10 s of atmospheres by evaporating water from nanoscale pores, sucking water up 100m in a state where it should be boiling but can t because the perfect xylem tubes contain no air bubbles, just so that most of it can evaporate in the process of absorbing a couple molecules of carbon dioxide. Now I didn t mention the cohesion of water (that it sticks to itself well) but this is implicit in the description of negative pressure, strong surface tension etc.