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Default defrosting windscreen


Alan wrote:
erm, no it won't - think about the chemistry first.

Ice is a lattice structure (like a diamond), and it takes energy for
the molecules to move into the lattice. In hot water, the molecules
are moving rapidly, and can therefore form the lattice quicker than
cold molecules which have very little energy.

That's why I said go and try it if you don't believe me - 2 containers
of water in a freezer (one hot, one cold), the hot one will freeze
faster than the cold one.

I've done it many times.


Hey - that's physics, not chemistry.
Another explanation is that the hot container melts any frost and is in
much better contact with the freezer's cooling tubes. The cold
container is sitting on a nice insulating blanket so can't lose heat as
quickly. It's also been suggested that the hot container has
convection currents and is more turbulent by the time it's cooled down
to the same temperature as the cold one was, and from there freezes
more quickly.

--
LSR