Speaker 1: Welcome to brain Stuff from how stuff works dot com
Speaker 1: where smart Happens. Hi, I'm Marshall Brain with today's question,
Speaker 1: what a balloon filled with vacuum instead of helium float?
Speaker 1: At sea level? Air weighs about one point to five
Speaker 1: grams per leader. A leader of helium, on the other hand,
Speaker 1: weighs about point one eight grams. If you weigh a
Speaker 1: one leader bottle filled with air and then weigh the
Speaker 1: same bottle filled with helium, it will weigh about one
Speaker 1: gram less. If the bottle itself weighed less than a gram,
Speaker 1: you couldn't weigh it at all because it would float.
Speaker 1: You would have to turn the scale upside down and
Speaker 1: put it above the floating bottle to check its negative weight. Generally,
Speaker 1: a balloon has to be several leaders in size before
Speaker 1: that one gram per leader weight difference of helium versus
Speaker 1: air is enough to overcome the weight of the balloon
Speaker 1: itself and float. If you could somehow fill a one
Speaker 1: leader bottle with a vacuum, it would float even better.
Speaker 1: A perfect vacuum ways zero grams, so a leader of
Speaker 1: perfect vacuum ways zero grams, and that's point one eight
Speaker 1: grams less than a leader of helium. The problem, of course,
Speaker 1: is that building a lightweight container that can hold a
Speaker 1: vacuum is not nearly as easy as building a container
Speaker 1: that can hold helium. The phrase nature of horrors of
Speaker 1: vacuum sums it up nicely. If you could figure out
Speaker 1: a way to do it, however, you could be set
Speaker 1: your vacuum balloon would float even better than a helium balloon.
Speaker 1: Not that you don't need to have a perfect vacuum
Speaker 1: for this to work. Any air that you take out
Speaker 1: of the container helps a vacuum balloon to float. Do
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