On the subject of
dropping objects from high places:
> On
Feb. 13 a single-engine Cessna flew low over the Utah desert toward the
>
Bonneville Seabase at 80 knots. Pilot Patrick Wiggins checked his
altimeter.
> As planned, he was just 820 feet (250 meters)
above the surface.
At
this low altitude, the bowling ball would only have reached a velocity
of
70
m/sec in a vacuum -- a bit less going through air. But
isn't typical
terminal
velocity
for a good-sized meteorite more
like 200 m/sec? If so, then the
drop
altitude would need to be over 2000 meters (over 6500 feet) to
reach terminal
velocity.
> Wiggins hopes to
make the next drop at more than a half-mile up (1,000 meters),
>
from where an object should achieve "terminal velocity," or top vertical
speed,
>
zooming straight down and having lost all its horizontal movement induced
> by the airplane ride.
At 1000-meter altitude, the bowling ball only has time to get
up to 140
m/sec,
which
is
probably fine for a smaller meteorite, but larger ones will be
faster.
--Rob
