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if i put a balloon on the moon that has hellium
and if i pop it ? where does the hellium goes?
Palisades Park High School
The moon has no atmosphere to speak of. (There might be a few molecules
knocked off from time to time by sunlight, but nothing much). So
there's no buoyant force on a balloon, whatever its contents. The
helium balloon will just fall to the moon with the same lunar rate of
gravitational acceleration (about a seventh of that on the surface of
the Earth) as anything else.
If you pop the ballon, the helium will expand into space -- the
molecules will go off in all directions. Some will bounce off the
surface of the moon and head back the other way.
(republished on 07/19/06)
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