Why would a lightning-struck tree glow after being hit?
It is not on fire and does not give off heat, but glows.
It was a dark and stormy night. Chris emails he
was walking in the woods "a little after a thunderstorm" when he
noticed the tree. The tree, shattered by an earlier lightning
stroke, stabbed the night like a broken pike. An eerie glow extended ...
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Wind chill doesn't affect inanimate objects
 Does
wind chill have an effect on inanimate objects? For example will the wind chill
have an effect on concrete setting up? Sam, Columbus, Ohio
Windbeeches in Germany's Black Forest. Photo courtesy of Richardfabi and
Wikipedia.
Wind chill doesn't affect inanimate objects, Sam, in the
same way as it does animate ones. Wind chill blows away the thin layer of air
next to our skin that we've warmed with our body heat. That makes us feel cold.
But, wind chill rarely has a similar effect on an inanimate object, which, in
general, can't warm
the thin layer close to its surface. However, wind could effect the setting up
of concrete, because wind fosters evaporation. In fact, we generally put wet
sacks over concrete so the concrete doesn't dry out as it sets up.
Comments:
- Let us not forget that concrete produces heat during the chemical reaction
of curing. The concrete like brick mortar sets up faster in warmer weather. It
also freezes when it gets cold enough. This is where wind chill comes into
effect. Notice I said when it gets cold enough not when it gets below 32F.
That's because it has it's own heat from the chemical reaction. The exact
freeze temp would depend on temperature, wind chill and amount of mortar or
concrete. The more concrete or mortar, the more heat.
Mike, Mchenry, Illinois
Further Reading
(Answered Feb. 25, 2008)
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