windshield fluid sprayer

Phil Payne quattro at
Thu Nov 29 20:50:31 EST 2001

> Once, while skiing, an ex-engineer demonstrated an interesting
> phenomena around boiling water and cold temperatures.
> At -40 degrees (figure it out, C or F), take a bucket full of
> almost boiling water, and fling the water in the air.
> Guess what happens? (hint: not what you think)

The hot freezes first because excess pressure inside a droplet is T/r, where T is the surface tension and r is the radius.  Two
effects - surface tension is lower at high temperatures and there is energy available as heat, so much smaller droplets can form.

Mass per unit surface area is less, so freezing is faster.

  Phil Payne
  +44 7785 302 803
  +49 173 6242039

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