
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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Why cyclones spin clockwise
Cyclone
Heta rotates clockwise in the Southern Hemisphere. Photo courtesy of NASA.
Continued from
Why
hurricanes spin counterclockwise (and cyclones clockwise): It's much the
same in the Southern Hemisphere. Suppose the cyclone's low pressure area is off
the coast of Samoa in the South Pacific at the spot marked 'L' in the diagram.
Higher pressure air from the north, west, east and south will move towards the
low pressure L as depicted by the white arrows. But the air to the south moves
slower than the low pressure area (since it's closer to the pole), and lags to
the west. Moreover, the air to the north moves faster, and speeds ahead to the
east. The different speeds cause the air to circulate clockwise about the low.
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